Method for accelerated bioremediation and method of using an apparatus therefor

ABSTRACT

This invention relates to a method of using an apparatus is provided for the accelerated bioremediation of treated contaminated material. The material is treated with chemical and/or biological amendments for facilitating accelerated bioremediation thereof. The apparatus comprises a system for for generating a treated contaminated material entraining air stream at a predetermined velocity for entraining the treated contaminate material therein for microenfractionating the treated contaminated material. In this way, accelerated bioremediation is facilitated. In another form of the invention, a method of accelerated bioremediation of treated contaminated material is provided. This method comprises the steps of (a) treating the treated contaminated material with chemical and/or biological amendments for facilitating accelerated bioremediation thereof, (b) providing an entraining air stream having a sufficient velocity for entraining the treated contaminated material therein, (c) entraining the treated contaminated material in the air stream, (d) microenfractionating the treated contaminated material, and (e) discharging the microenfractionated treated contaminated material from the air stream. In this way, the treated contaminated material can be acceleratedly bioremediated.

RELATED APPLICATION

This is a continuation-in-part application of U.S. Ser. No. 08/043,666,filed Apr. 6, 1993, now abandoned which is a divisional application ofU.S. Ser. No. 07/918,528 now abandoned, filed Jul. 21, 1992.

BACKGROUND OF THE INVENTION

The present invention relates to a method for the acceleratedbioremediation of contaminated material and to a method of using anapparatus therefor, and more particularly to the acceleratedbioremediation of contaminated material treated with chemical and/orbiological amendments.

Bioremediation in general involves the degradation of contaminatedmaterial, typically by the action of contaminate degrading aerobicbacteria. When practiced on a small scale, it is relatively easy tomaintain the aerobic conditions required by the bacteria; it is muchmore difficult to do on a larger scale. Failure to maintain aerobicconditions throughout the contaminate material results in anaerobicdecay of the material, which is much less efficient and much more timeconsuming than aerobic decomposition. This provides strong incentive tomaintain aerobic reaction conditions at all times.

The biological degradation of hydrocarbons can be conducted employingspecialized bacteria that utilizes hydrocarbons as their sole metaboliccarbon source or as a co-metabolite. The bacteria produce enzymes whichcatalytically crack the covalent carbon-hydrogen bonds of hydrocarbonsso that the smaller resulting molecules may pass through the cell wallof the bacterial organism for nutrient. In some instances, the bacteriamay produce enzymes which crack a carbon bond on an alternate carbonsource such as a carbohydrate. This same enzyme may also crack thehydrocarbon. This is called co-metabolism.

In addition to a carbon source, most living organisms require a balanceof other nutrients such as nitrogen, phosphorus, various minerals inmicro quantities, etc. to efficiently metabolize and reproduce. Anyspecific nutrient that is deficient in a given biological system willlimit the efficiency of that system. This is akin to the "basic 4 foodgroups" idea of human nutrition which includes protein as a nitrogensource, carbohydrate as a carbon source, dairy as a fat or fatty acidsource plus phosphorus and a large number of vegetables as a vitamin andmineral source. Although bacterial requirements may be different fromhumans, a balanced nutritional system is required for optimal bacterialactivity.

There are thousands of identified sites in the United States containinghazardous wastes. For most of these sites, the recognized methods forclosure are:

1. Cap and store-in-place

2. Removal to an approved hazardous waste landfill.

3. Solidify in place with fixation chemicals

In addition to the methods generally known, many industrial plants haveused biological solutions to effect closures. Quite a few biologicalcleanups took place prior to the effect of the RCRA and TSCAlegislation. Now under the formal guidelines of current hazardous wasteregulation, use of biological treatment can offer an economicalalternative to the methods listed above.

Biological treatment of hazardous waste chemicals can take the followingforms:

1. Treatment of industrial wastewater through biological oxidation underan NPDES permit.

2. Treatment of on site chemicals through controlled release to anNPDES-permitted system (many states allow this through a temporarypermit amendment).

3. Treatment of leachates collected under hazardous waste sites. In somecases a cone of depression can be created to leach organics out at arapid rate.

4. Land farm of sludges and solid-containing organics.

Land farming is of principle interest due to the large numbers of areasites with contaminated sludges and soils.

A key issue in a hazardous waste site closure is permitting land farms.Often obtaining such a permit is not feasible under existingregulations. In most cases, those regulations were intended to addressnew land farms. Land farming is a biochemical process which operates atlow biological reaction rates. The variables controlling total cleanuptime in a land farm are initial substrate concentrations, desiredtreatment levels, area available for land farm and turnaround time todispose of decontaminated sludge or soil. Many hazardous waste sitescould be successfully land farmed in 6-12 months, after pilot work iscomplete.

The actual protocol for land farming a particular site should beestablished for each site by a combination of pilot testing andpractice. A typical protocol for land farming a hazardous waste sitewould be as follows:

1. CHARACTERIZATION OF THE SITE

This includes additional soil borings, groundwater monitoring andchemical analyses to determine the site contamination characteristics.

2. CHARACTERIZATION OF THE ORGANICS AS TO BIODEGRADABILITY

This is usually researched into the treatability of chemicals found inthe site.

3. CHARACTERIZATION OF THE SOIL

The soil must be analyzed for pH, macronutrients (N,P,K), micronutrients(usually trace metals), permeability, moisture content and otherconditions which will determine its suitability for land farming.

4. CRITERIA FOR SUCCESSFUL LAND TREATMENT

A chemical protocol is established to allow monitoring of the land farm.This is a two-tier protocol consisting of:

A. Control analyses to allow quick determination of treatment progressduring the land farming.

B. Objective toxicity testing to be used when control analyses indicatethat the treatment is complete. This includes all testing for leachatepriority pollutants.

5. BENCH SCALE LAND FARM TREATMENT

Using the site characteristics, the land farm is simulated andefficiency of the treatment is proven. Samples of decontaminated soiland sludge may be presented for reference analyses.

6. DESIGN OF LAND FARM TREATMENT

The consultant and land farm specialists designate the portion of theclosure site to be used for the land farm and design excavationschedules, aeration and mixing techniques, irrigation method, run-offcollection, and decontaminated soil removal and disposal method.

7. IMPLEMENTATION OF LAND FARM TREATMENT

Beginning with a surface treatment of the site to be used, the land farmis begun. After control testing shows a desired level of treatment,toxicology tests are made. The soil may then be decontaminated andremoved, if desired. Land farming is then usually continued in 12"lifts.

8. CLOSURE

Decontaminated sludges and soils are removed to a nonhazardous wastelandfill or landfilled on-site.

The above steps are difficult and timely in their performance andextremely costly to the end user.

There are known machines for physically mixing materials in the fieldsuch as compost to maintain aerobic conditions. An example is U.S. Pat.No. 4,360,065 to Jenison et al. The Jenison cultivator comprises ahorizontal rotating drum having a plurality of cultivator blades in twohelical rows. As the drum is rotated, the blades travel edgewise througha pile of composting material to move the material sideways and pile itin a generally triangular pile. The '065 patent further describes othercomposting machines such as the Scarab, sold by Scarab Manufacturing andLeasing, Inc. of White Deer, Tex. U.S. Pat. No. 3,369,797 to Cobeydescribes a compost turner and windrow forming machine having atransversely mounted rotating drum for the turning of compost piles andthe redepositing of the turned up material in a windrow. Yet anothercomposting apparatus is described in U.S. Pat. No. 4,019,723 toUrbanczyk. The '723 patent describes a mobile composter for manure whichmoves a rotating drum over masses of inoculated manure to flail it, mixit, cool it and aerate it, while moistening the particles as the sametime. After being conditioned and moisturized, the material is formedinto a pile by a rear outlet opening. As with the Cobey composter, theflails mounted on the drum of the Urbanczyk machine travel edgewisethrough the composting material for flailing and mixing. U.S. Pat. No.4,478,520 also to Cobey describes a compost turning machine whichstraddles a compost windrow while carrying a rotating drum for turningthe composting material. The '520 composter additionally has an adjusterauger system outboard of the rotating drum to collect additionalmaterial and deposit it in the path of the rotating drum. This is theCobey machine referred to earlier.

A need therefore exists for a method of bioremediation which willovercome the problems associated with the above described prior artmethods by substantially eliminating the contaminants from contaminatedmaterial in an effective, efficient and accelerated manner.

SUMMARY OF THE INVENTION

Applicants have met the above-described existing needs and have overcomethe above-described prior art problems through the invention set forthherein.

In one form of the invention, a method of using an apparatus is providedfor the accelerated bioremediation of treated contaminated material. Thematerial is treated with chemical and/or biological amendments forfacilitating accelerated bioremediation thereof. The apparatus comprisesmeans for generating a treated contaminated material entraining airstream at a predetermined velocity for entraining the treatedcontaminate material therein for microenfractionating the treatedcontaminated material. In this way, accelerated bioremediation isfacilitated.

Generally, the means for generating a treated contaminated materialentraining air stream at a predetermined velocity comprises an elongatedrum having a longitudinal axis, first and second end portions, and acenter portion. The drum is rotatable about its longitudinal axis at apredetermined rotational speed, and means extending outwardly from thedrum are provided for generating the treated contaminated materialentraining air stream. Preferably, the treated contaminated materialentraining air stream comprises a plurality of air currents, and the aircurrent generating means comprises a plurality of paddles extendingoutwardly from the cylindrical outer surface of the drum. Typically,each paddle comprises a base portion connected to the drum, and a bladeportion. Each blade portion has a major surface oriented for generatingat least one the air current having a sufficient velocity for entrainingand transporting treated contaminated material upwardly of the rotatingdrum when the drum is rotated at the predetermined rotational velocity.

The treated contaminated material entraining air stream preferablycomprises a plurality of intersecting air currents. Each of theintersecting air currents has a sufficient velocity for entraining andtransporting a portion of the treated contaminated material upwardly ofthe air stream generating means. More specifically, the means forgenerating a plurality of intersecting air currents comprises aplurality of end paddles extending radially outwardly from the first andsecond end portions of the drum. Each end paddle can comprise a baseportion connected to the drum and a blade portion. In this instance, theblade portion has a major surface oriented relative to the drum forgenerating an air current directed upwardly of the drum and transverselytoward the center portion of the drum when the drum is rotated at thepredetermined rotational speed. It also has a plurality of centerpaddles extending radially outwardly from the center portion of thecylindrical outer surface. Each center paddle comprises a base portionconnected to the drum, and a blade portion having first and second majorsurfaces. The first and second major surfaces are oriented relative tothe drum for generating an air current directed upwardly and rearwardlyof, and transversely toward the first and second end portions of thedrum respectively when the drum is rotated at the predeterminedrotational speed. In use, the air currents generated by the end andcenter paddles intersect and combine to form the treated contaminatedmaterial entraining air stream for microenfractionating the treatedcontaminated material.

In a preferred embodiment, the treated contaminated material entrainingair stream comprises a vortex-type air stream which transports theentrained treated contaminated material in a generally circular path. Inthis case, the end and center paddles can extend radially outwardly fromthe drum so that they are arranged in a plurality of helicallongitudinal rows. Also, the drum can further comprises first and secondtransition portions disposed between the center portion and the firstand second end portions respectively. The first and second transitionportions of the drums having a plurality of end paddles and a pluralityof center paddles extending radially outwardly therefrom.

In another form of the invention, a method of accelerated bioremediationof treated contaminated material is provided. This method comprises thesteps of (a) treating the treated contaminated material with chemicaland/or biological amendments for facilitating accelerated bioremediationthereof, (b) providing an entraining air stream having a sufficientvelocity for entraining the treated contaminated material therein, (c)entraining the treated contaminated material in the air stream, (d)microenfractionating the treated contaminated material, and (e)discharging the microenfractionated treated contaminated material fromthe air stream. In this way, the treated contaminated materialacceleratedly bioremediated. The microenfractionating step preferablycomprises homogenization and aeration of the treated contaminatedmaterial. The entraining air stream preferably comprises providing anentraining air stream including a plurality of upwardly and transverselyflowing, intersecting air currents, and more preferably comprises avortex-like entraining air stream. Typically, the step of providing anentraining air stream includes the step of rotating a drum assembly at arotational speed sufficient for generating the entraining air stream.The drum assembly can include means for generating this plurality ofintersecting air currents when the drum assembly is rotated.

In one preferred method, the treated contaminated material iscontaminated with a hydrocarbon material, and the acceleratedbioremediation of the treated contaminated material comprisesaccelerated chain scission of the hydrocarbon material. In another case,when the treated contaminated material is contaminated with hydrocarbonmaterial, the accelerated bioremediation produces CO₂ and water (H₂ O)from the treated contaminated soil and purges CO₂ therefrom. A furtherinstance is where the treated contaminated material is contaminated withhydrocarbon material, and the accelerated bioremediation comprisesreduction of the total hydrocarbon material in the treated contaminatedmaterial.

In general, at least about 70%, preferably at least about 80%, morepreferably at least about 90%, and most preferably at least about 95% ofthe accelerated bioremediation of the treated contaminated material iscompleted within 150 days, preferably within 120 days, more preferablywithin 90 days, and most preferably within 60 days. Moreover, the volumeof treated contaminated material which is acceleratedly bioremediatelytreated by the method of the present invention is generally at leastabout 1500 cubic yards, preferably at least about 2000 cubic yards morepreferably at least about 2500 cubic yards, most preferably at leastabout 3000 cubic yards, per day per apparatus.

The method of this invention can further include the step of adding woodparticles to the treated contaminated material prior to themicroenfractionating step. This assists in microenfractionation andallows the user to visually determine the extent to which the treatedcontaminated material has been redistributed over a given soil matrixarea. The amount of wood particles which can be added to the treatedcontaminated material prior to the microenfractionating step ispreferably up to about 20% by volume, based on the total volume of thetreated contaminated material.

The method of the subject invention produces high surface area treatedcontaminated microenfractionated material. The surface area of thetreated contaminated non-microenfractionated material can be increased,after the microenfractionating step, as compared to the surface area ofthe treated contaminated non-microenfractionated material, by a factorof at least about 1×10⁶, preferably at least about 2×10⁶, morepreferably at least about 3.5×10⁶, and most preferably at least about5×10⁶. More specifically, the subject method can further include thestep of discharging the microenfractionated treated contaminatedmaterial from the air stream and redistributing it throughout a soilmatrix. In this manner, the surface area of the microenfractionatedtreated contaminated material is substantially increased. This isespecially important when dealing with clay type soils.

Most prior art remediation processes cannot be conducted at ambienttemperatures below 10 degrees C. However, when the method of the subjectinvention is employed, the aforementioned high degree of acceleratedbioremediation can be maintained at an average ambient temperature whichis not more than about 10 degrees C., preferably not more than about 7degrees C., more preferably not more than about 3 degrees C., and mostpreferably not more than about 1 degree C.

One reason why the accelerated bioremediation of this invention can beconducted at the low ambient temperature conditions described in thepreceding paragraph herein, is that the subject reaction is generates amore substantial amount of exothermic heat than known prior artremediation processes. Thus, the accelerated bioremediation ispreferably conducted at an exothermic temperature measured within thecontaminated material of at least about 5 degrees, and more preferablyat least about 10 degrees, higher than an average ambient airtemperatures of from about zero up to about 10 degrees C.

As for the treatment of the contaminated material with the chemicaland/or biological amendments, it is preferred that they are dispersedthroughout the redistributed microenfractionated treated contaminatedmaterial thereby facilitating accelerated bioremediation. The chemicaland/or biological amendments are preferably substantially organic innature. In conventional treatment, inorganic materials are added to thecontaminated material and react to form, over time, the organicmaterials required in the bioremediation process. This time lag from theintroduction of inorganic materials onto the treatment area and theformation of organic material and the initiation of a significantremediation thereof is defined as an induction time. In the method ofthe present invention, the induction time for converting inorganicamendments into organic amendments for conducting the acceleratedbioremediation is substantially zero.

Other preferred embodiments of the subject method include (a) locatingan impervious undercover below the treated contaminated material priorto the microenfractionating step thereby preventing the chemical and/orbiological amendments from leaching into soil underlying the treatedcontaminated material, and (b) a cover over the microenfractionatedtreated contaminated material, the cover allowing substantial solarradiation to pass therethrough and into the microenfractionated treatedcontaminated material, thereby facilitating the acceleratedbioremediation and preventing moisture from soaking themicroenfractionated treated contaminated material and to preventmoisture evaporation from the microenfractionated treated contaminatedmaterial.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a front view of the preferred apparatus for use in the presentinvention.

FIG. 2 is a rear view of apparatus of the apparatus of FIG. 1.

FIG. 3 is a left side view of the apparatus of FIG. 1.

FIG. 4 is a right side view of the apparatus of FIG. 1.

FIG. 5 is a top view of the apparatus of FIG. 1.

FIG. 6 is a top view of the apparatus of FIG. 1 configured for beingdriven sideways.

FIG. 7 is a front view of the apparatus of FIG. 1 configured for beingtowed sideways.

FIG. 8 is a right side cross-sectional view of the drum and paddleassembly according to the present invention.

FIG. 9 is an enlarged sectional view of the center portion of the drumand paddle assembly, showing the counter-rotating vortex-like airstreamsgenerated when the assembly is rotated.

FIG. 10 is a top view of a right side paddle.

FIG. 11 is a top view of a center paddle.

FIG. 12 is a top view of a left side paddle.

FIG. 13 is a side view of a right side paddle showing the shear pinfeature, and showing the released paddle in phantom.

FIG. 14 is a front perspective view of a contaminated materialeraccording to the present invention, having the drapes removed to exposethe chamber and drum assembly.

FIG. 15 is a top view of windrows formed in the treated contaminatedmaterial prior to microenfractionation.

FIG. 16 is a side view of windrows formed in the treated contaminatedmaterial prior to microenfractionation.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

The method of the present invention differs from the prior art in thatit approaches bacterial activity from a total nutritional point of view.The subject method employs chemical and/or biological amendments thatare organic in nature, and are nutritionally balanced to provide all ofthe nutrients required to efficiently biodegrade whatever the materialcontaminant is present. Preferably, the material contaminant is anorganic molecular contaminant. In addition, these chemical and/orbiological amendments are preferably partially water soluble to preventthem from migrating away from the contaminated areas. Migration of priorart chemicals such as ammonium nitrate, for example, will move fiveinches in sandy soil for every inch of water applied. Also, undercertain pH conditions like alkaline, phosphates move very little. Basedon these two characteristics, the nutrients required by bacteria willnot be effectively and efficiently available or in balance in aninorganic nutrient system.

One area of bioremediation often overlooked is adequate balance of thecontaminated soil with nutrients and bacteria. In order forbioremediation to function, a total and complete balanced nutrition isrequired. Correct selection of bacteria degraders, neutral balance of pHin both soil and all liquids being added to the soil, and adequatewater, oxygen and temperature are also essential. If any of thesefactors is not within certain parameters, the bioremediation will eitherbe slowed down or fail.

A proprietary process of activating commercial bacteria has beendeveloped in such a manner that viable cell counts are high enough inmany instances to nearly eliminate the normal lag time. Proof of this isdemonstrated by monitoring the dissolved oxygen uptake rate of thebacteria undergoing activation. The more viable cells metabolizing, themore oxygen required for metabolism. Thus a very high dissolved oxygenuptake rate indicates a large, healthy bacterial population while lowdissolved oxygen uptake rate numbers indicate the reverse.

In the ex-situ method of this invention, the soil should be removed fromthe contaminated site and placed in windrows on top of durable linerwhich acts as an underliner in the subject accelerated bioremediationprocess. This underliner substantially prevents undesirable materialspresent in the ex-situ soil from leaching into the surroundinguncontaminated soil prior to the completion of the bioremediationprocess. It has been determined that a woven polyolefin fabric of thetype exemplified by NOVA-THENE® RB616-6HD, manufactured by PolymerInternational (N.S.) Inc., of Truco Nova Scotia, Canada, is one of themost durable liners available for this purpose. One reason is that itwill remain intact during the microenfractionation of the treatedcontaminated material by the hereinafter described subject apparatus.

After the liner has been laid down in a pile (on as smooth a surface aspossible), a layer of sand is applied over the liner. If there are claytype soils, wood particles such as chips or sawdust are put down onliner before contaminated soil introduced and formed into windrows asshown in FIGS. 15 and 16. The sand or wood particle layer will permitcomplete mixing of all of the contaminated material and will overcomesoil stratification. Windrows are typically spaced 6-8 feet apart. Thewindrows should be no wider than 14 feet and no higher than 6 feet. Theabove-described liner is extended out 4 feet past edge of pile with aberm of about eight inches to allow the microenfractionating equipmentto straddle the pile. All rocks, chunks of concrete larger than twoinches and other debris should be removed from contaminated soil priorto microenfractionation. Once the contaminated dirt has been windrowed,treatment with the chemical and/or biological amendments can commence.

SOIL ANALYSIS PRIOR TO STARTING TREATMENT

First, the soil is analyzed for contaminant, and a full agriculturalanalysis is done. The testing for total petroleum hydrocarbons is not initself an easy task. The type and quantity of contaminant must beaccurately revealed. The contaminant reduction requirements must also beknown. In addition, a series of soil tests must be undertaken. Thesetests include, but are not limited to, the following:

1. Total Petroleum Hydrocarbon Levels: The amount and nature of thehydrocarbon contaminants in the soil must be first determined. Theseinclude BTEX, PCP, PAH, PCB and the like.(EPA Test Nos. 418.1, 8015,8020, etc.)

2. Standard 1/3 Bar Moisture Retention: The test will ascertain thequantity of water this soil will retain when placed under 1/3 barvacuum. This is a standardized test to determine the saturation point ofthe soil with water. Knowing this will assist in determining thequantity of moisture that can be reasonably utilized during soiltreatment.

3. pH: This test will determine if the soil is acidic, basic or neutral.Neutral pH is best for biological degradation. If the soil is either tooacidic (i.e. pH 6.0 or below), soil amendments will be necessary to makethe soil pH more neutral (7.0 pH). If the soil is too basic (i.e. pH 8.0or above), again, soil amendments will be necessary to make the soil pHmore neutral.

4. Standard Buffer Capacity: This test will determine how much acid orbase can be introduced into the soil before a pH change occurs. Thisinformation is useful because soil amendments can alter pH as canbiological metabolyte materials produced during the biological treatmentof petroleum hydrocarbon contaminated soil.

5. Standard Electrical Conductivity: Bacteria require a certain amountof electrical conductivity to survive and metabolize nutrients. If thereis too little electrical conductivity or too much, the biological systemcan be inhibited or destroyed. Again, soil amendments can alterelectrical conductivity if it becomes necessary.

6. Standard Sodium Absorption ratio (SAR): This test determines anestimate of the exchangeable sodium percentage of what a soil is, orwhat it is likely to become if the water that comprises the sample wateris in that soil for long periods of time. The SAR has a good correlationto the exchangeable sodium percentage and is easier to calculate exactly(or to estimate from a few simple analysis) than is exchangeable sodiumpercentage. If the SAR exceeds 13, the biological system will be greatlyimpaired.

The purpose for the test is to determine if too much salt in the soilwill inhibit biological activity by having sodium ions occupy a highproportion of exchange sites in the soil causing high pH and low waterpermeability. If this situation occurs, biological activity will slow orcease. Note that the use of inorganic nutrients can promote high saltcontent in soil due to the salt nature of inorganic nutrients. Organicbased nutrients do not cause this to happen because they are not saltbased.

7. Standard Organic Matter: Organic matter is required for anybiological system to function properly. The organic matter can be amedia of bacteria, it can supply nutrients in some cases, and it can bean indicator of biological activity. Knowing the organic matter levelcan help determine if additional organic matter is needed for soilstreatment.

8. Standard NPK or the Soils Nutrient Tests of Nitrogen, Phosphorus,Potassium: These are the three major or macro-nutrients required forbacterial growth. The pretreatment levels of these nutrients must beknown to balance the nutrient addition properly. Hydrocarboncontaminated soil is frequently very deficient in one or moremacro-nutrients.

9. Standard Micro-nutrient Profile of the Soil: In addition tomacro-nutrients, a micro-nutrient profile of the soil is very useful.Macro-nutrients are elements such as sulfur, copper, iron, zinc, boron,manganese, sodium, magnesium and calcium. All of these elements arenecessary for microbial growth in very small quantities. If one or moreof these nutrients are absent or unavailable, bacterial activity isinhibited. Conversely, if one or more micro-nutrients is excessive, thiscan also be inhibitory on bacterial growth. Micro-nutrients are elementsin trace quantities required by organisms for metabolism. This must beknown. The soil type of the contaminated soil must be ascertained, i.e.percentage of sand, silt, or clay. Each soil type must be treateddifferently. For instance, straight sand may not be capable of retainingmoisture; clay or fine silt may require the addition of sand or woodfiber to assisting in breaking the soil platelets apart, so that oxygenis not excluded from the system.

10. Other tests: Moisture content and temperature determinations shouldbe made in order to determine if environmental conditions are conduciveto biological activity.

11. Other Contaminant Sources: One last bit of information about thesoil to be treated is very useful. It must be known if any otherchemical or element is contaminating the soil in addition to thehydrocarbon contaminant. A good example of this is arsenic contaminatedsoil in the Pacific Northwest. This type of contamination can be naturalor artificially introduced. Unfortunately, in high enough concentration,this type of contamination can greatly inhibit the necessary biologicalactivity required for remediation. Not only is it important to know thequantity and type of additional contaminant but also the percentleachable. If the contaminant is not very leachable, it won't affect thebiological system to the same extent as if the contaminant was moreleachable.

EX-SITU SOIL TREATMENT

Ex-situ treatment is the removal of contaminated material to a secondsite, and the remediation of thereof at that second site. In providingthe second site, a berm is made typically from soil, straw or concreteecology blocks. The width and length is dependent on the area availablefor use in bioremediation. First, the area contained by the berm issmoothed. It is then covered with the above-described underliner inorder to create an impermeable barrier between the contaminated soil andthe uncontaminated soil. Next, the underliner is covered with 2-4 inchesof fine sand or pea gravel or wood chips. Then, the windrows ofcontaminated soil 14 ft.wide and 6 ft. tall are laid out. Space must beleft at sides and ends of berm for maneuvering the microenfractionatingequipment. Finally, the entire windrow layout is covered with atranslucent outdoor material which permits solar radiation to passtherethrough. The preferred material for this purpose is Loretex 1212 UV(clear), manufactured by Chave & Earley, Inc. of New York City, N.Y., awoven polyethylene substrate coated with polyethylene which ismanufactured by The Loretex Corporation.

TREATMENT OF CONTAMINATED MATERIALS

The soil is prepared by first adjusting the pH to between about 6.0 and8.0, preferably between about 6.5 and 7.5, and most preferably about7.0, and is then treat with the chemical and/or biological amendments.

From the biological standpoint, a balance biological diet designed toenhance and accelerate degradation of hydrocarbon contaminants can befirst provided. For instance, HH MICRO-2 or HH MICRO-51D manufactured byH & H Eco Systems, Inc. is mixed with the contaminated soil 24 hours inadvance of adding bacteria. Both the HH MICRO-2 or HH MICRO-51D compriseAcidified Fish (nutrient), a sulfated molasses co-metabolite whichfacilitates enzyme production (sulfur and sugar), ammonium nitrate (N₂source), BNB micronutrients, fragrance enhancers, and xanthan gum(prevent separation). BNB is a trademarked proprietary productmanufactured by Westbridge Agricultural Products of Carlsbad, Calif.,and comprises a blend of micronutrients, microbiological growthstimulators, and microbiological growth regulators. It is a concentratedmicrobial growth medium derived from waste products from the foodindustry and animal origin combined with micronutrients. A typicalrecipe for the HH MICRO-2 or HH MICRO-51D biological nutrients having aboiling point of 216 degree F., a specific gravity of 1.21, and a %volatile by weight of 26.8, comprises the following: 411 kg. of Fish OP4(Acidified), 60 kg. of Molasses (Food Grade), 141 kg. of 32-0-0 AmmoniumNitrate, solution (32% nitrogen, 0% phosphorus, and 0% potassium) and0.3 kg. of Kelzan-s Xanthan Gum (plus a fragrance enhancer). Therequirements for the biological diet will be made from the soil analysisand TPH levels in the soil. In general, a total of from about 0.5 to 2.0liters per cubic meter of the biological material is added to thecontaminated material in order to achieve the maximumcost-to-effectiveness relationship regarding facilitation of theaccelerated remediation.

H & H Eco Systems, Inc. is also the distributor of hazardous wastedegrading bacteria. These bacteria are generated from cultures found innature, and they are capable of degrading many organic compounds.Examples of these bacteria include Solmar, ERI, BioScience and allproprietary trademarked formulas comprising pseudomonades and/or bacillisp., such as various strains of pseudomonas aeruginosa and/or bacillussubtilis, manufactured by Westbridge of Carlsbad, Calif. The bacteriashould be checked to determine the formula most appropriate for specificsite. Due to the cost of such bacteria, only from about 0.5 to 5 ouncesof a bacteria such as AGRI-SC is employed in the subject chemical and/orbiological amendments. The bacteria are typically started 12 hours inadvance of soil application. Here is a typical procedure for startingthe bacteria:

a. Add water at a rate of 1.5 gallons for each 1 lb. of bacteria

b. Add HH MICRO-2 or HH MICRO-51D nutrient at recommended rate for thegiven site.

c. Add 1/2 lb. of contaminated soil to mixing tank.

d. Add air to mixing tank until applied in 6-12 hours.

After the pH of the contaminate soil is balanced, apply balancedbiological diet and mix thoroughly. Apply the bacteria. The pile shouldbe covered with Loretex 1212 UV. The soil temperature should preferablyremain above 7° C. and below 38° C. for the bacteria to remain active.Lower temperatures may cause the bacteria to revert back to theirdormant stage and higher temperatures will degrade or kill the bacteria.A minimum of about 20%, up to about 40% moisture, and preferably fromabout 25% moisture up to about 35% moisture, and most preferably about30% moisture, is required for accelerated bioremediation.

Regarding soil types, in heavy clay or silt add alder or firwood chips,or pea gravel. Alder or fir sawdust can also be used. In sandy soil,there are no additional requirements.

TREATMENT CELL CONSTRUCTION

The treatment cell design of choice is a windrow configuration with thesoil pile dimensions. For example, a windrow configuration conforming to14 feet wide at the base, 5 feet wide at the top and a height of no morethan 6.5 feet. Windrow length is limited only to available space at agiven job site. The windrow should be placed on a level, smooth, firmsurface. An underliner of the must be used and must be a continuouspiece for surrounding environment protection. The edges of theunderliner must be bermed 8" to 10" to prevent any leachate that may beproduced during treatment form escaping. The berm material may vary, buta ridge of sand under the underliner and completely surrounding thecontaminated soil works very well. Typically, when using this treatmentmethod, no leachate collection basin has been necessary. By using sandor a similar textured material, the underliner covering the bermedsection can be driven on by the microenfracting apparatus without damageto the underliner.

If wood fiber is added, alder chips have preference. Cedar should not beused. The wood chips work most efficiently when a hard packed layer isinstalled (18" to 20") over the underliner prior to soil installation.This particular design allows the microenfractionating apparatus to belowered through the soil, into the wood chips, and provides forexcellent dispersion as well as 100% mixing of the treated contaminatedsoil. It also allows another benefit. By stirring midway through thewoodchips, the underliner is in no danger of damage from the machine.

After the underliner structure and windows are set up, the soilamendments--nutrients, surfactants, and bacteria (when necessary)--maybe added. The method for dispersion of soil amendment is via broadcastspraying by the H&H Eco Systems spray unit or equivalent.

A one piece top cover made from Loretex 1212 UV material is veryresistant to damage from solar radiation. This material also transmitsthe maximum amount of solar radiation to the contaminated soil, thusassisting with elevated soil temperatures required of the bacteria forrapid metabolism. This property is very useful in promoting bacterialactivity during periods of low ambient air temperature.

If the soil consists of clay, silt or any combination thereof, sand orwood fiber addition is highly recommended. Either of these substanceswill inhibit compaction of these "tight" soils. For very heavy clayconcentrations, i.e. fatty clay, wood fiber is recommended due to itssuperior clay platelet separation characteristics. The wood fiber willalso tend to generate heat as it degrades. This is a very usefulcharacteristic to enable the accelerated bioremediation process to workthrough the winter actively. Soil pile temperatures in excess of 21degrees C. have been generated during the winter where the ambienttemperatures ranged from -9 degrees C. to 5 degrees C. In all cases, thesoil texture was silt, silt and clay, or fatty clay. Although there areseveral other contributors to soil heat during degradation, such assolar radiation, biological energy from petroleum hydrocarbondegradation and heat from surfactant degradation, the wood fiber is avery significant factor.

CHEMICAL AMENDMENT

The addition of certain specific surfactants, when used in the properratios, assists in the dispersion of the hydrocarbons throughout thesoil, thus increasing the surface area of the contaminant to allow thebacteria to utilize the contaminant as a metabolite. As the surfactantsof choice are also biodegradable, the addition of the surfactants in acontrolled biosystem should pose no threat to the environment. Also,economically, the addition of the surfactant has very little impactbecause the concentrations rarely exceed 350 ppm per application.Additional benefits of the surfactant are its chelating properties thatmake the nutrients in the contaminated soil, whether natural or added,more available to the bacteria doing the contaminant degradation.

The surfactant system of choice for use in petroleum hydrocarboncontaminated soil is Simple Green® manufactured by Sunshine Makers, Inc.This material is very biodegradable and environmentally friendly. Inaddition, Simple Green® has a number of properties which make its useattractive for biodegradation of petroleum hydrocarbons. It haschelating properties which tend to make some nutrients more biologicallyavailable. Simple Green® also has the ability to chemically couple watermolecules with hydrocarbon molecules, thus assisting in thebioavailability of the hydrocarbon for bacterial metabolysis. About0.2-0.4 liters/cubic meter of the above-described surfactant seems to bean optimum amount for use in the chemical and/or biological amendment ofthe present invention.

NUTRIENT AMENDMENTS

Micro-nutrients, such as those produced by H & H Eco Systems, aredesigned to take advantage of bacteria's natural ability to control thebiosynthetic pathways. In order for bacteria to survive in a givenenvironment, i.e., an ex-situ biological treatment of hydrocarboncontaminated soil, the desired microflora must reproduce more rapidlythan any other organism in the same environment. H & H Eco Systems'nutrients are formulated to provide the desired microflora with as manyof the essential nutrients as possible.

Because the supply of available energy is generally the limiting factorin bacterial growth in nature, it is crucial that the bacterial cellsynthesize the maximum amount of cell material from a limited supply ofenergy. Bacterial cells may synthesize cell structure by elaboratecontrol mechanisms of their biosynthetic pathways. If the biosyntheticproducts of bacterial cells are present in large concentration, thebacterial cell can cease synthesis of these products for cell synthesisand utilize the products directly. If the organism can utilize ratherthan synthesize needed end products of biosynthetic reactions that maybe available from the environment, energy can be conserved. By utilizingorganic based nutrients in H & H micro products, the bacteria degradingthe petroleum hydrocarbons are actually providing the amino acids andother end products required for cell reproduction rather than requiringthe bacteria to synthesize their own end products.

If inorganic nutrients are utilized in a biological treatment ofpetroleum hydrocarbons, the bacteria must utilize a great deal of energyto synthesize the end products required for reproduction rather than themore efficient direct utilization of the H&H organic based nutrients. Byproviding a medium composed of amino acids/micro-nutrients/other endproducts of biosynthetic pathways, the hydrocarbon degrading bacterialcells actively take up these metabolites through their permease systemswhich requires a minimal expenditure of energy. Simultaneously, thecells close down their own biosynthetic routes thus conserving energy tochannel it in the rapid synthesis of macromolecules. Under theseconditions, the cells divide at their most rapid rate. By providing allof the tools necessary for the bacterial cells to produce themacromolecular catabolic enzymes required to degrade the hydrocarbon,H&H Eco Systems micro-nutrients ensure the most rapid reduction of thecontaminant. The other macromolecular structures include amino acidswhich is required for bacterial cell reproduction. If these buildingblocks are present, as they are in H&H Eco Systems micro products, themost efficient biological process results.

In addition, cells do not synthesize catabolic enzymes unless thesubstrates that these enzymes degrade are present in the environment.For this reason, the nutrients will act as a surrogate substrate for thestimulation of specific catabolic enzyme production by the bacterialflora for the express purpose of degrading petroleum hydrocarbons.

The nutrient amendments required for a specific job will depend on whatthe analytical workup described above indicates. The main ingredient toany nutrient supplement will be the HH micro product. H&H Eco Systemshas a number of formulations for specific contaminants and conditions.As previously indicated the micro products are primarily organic-basedand contain both macro- and micro-nutrients, as well as co-metabolytes,growth regulators and amino acids. These products have a very low pH(2.5 to 3.0) and should be neutralized to pH 6.0-8.0 prior for bestresults.

It has been determined that the most effective pH neutralizationcompound is 45% potassium hydroxide solution. This material is very easyto control chemically and has the added benefit of supplying additionalnecessary potassium to the biological system.

If the petroleum hydrocarbon concentration is very high, multiplenutrient and surfactant application may be necessary. The nutrient andsurfactant quantities recommended are based on carbon to nitrogenratios. However, high hydrocarbon contaminant levels are not a problemif the nutrients and surfactants are "metered in" with specific dosagesduring soil mixing operations. The surfactant should be kept at lowlevel, i.e., at less than about 1000 ppm, preferably less than 750 ppm,and most preferably less than 500 ppm total concentration, or it becomesinhibitory to bacteria. The H&H micro products are limited to 1000 ppmfor the same reason. Both may be added in multiple applications,however, because biological activity will consume both the nutrient andsurfactant while degrading the hydrocarbon. If wood fiber is used,additional wood fiber may be necessary during the course of theremediation because it will be degraded as well.

MICROENFRACTIONATION

Soil microenfractionation is one of the most critical aspects ofbiological treatment of petroleum hydrocarbon contaminated soils. Thereason this is important is that most petroleum hydrocarbon contaminatedsoil is very unevenly contaminated or fractions in nature. Thehydrocarbons will frequently form "globs" of contamination of highconcentration in the soil. These "globs" repel water as well asmaintaining a high enough concentration of petroleum hydrocarbon toinhibit bacterial growth except at the contamination interface. Thecontamination interface will generally provide conditions favorable forbacterial growth with both available water and relatively lowhydrocarbon concentrations. The biological degradation rate is thuscontrolled by the active surface area of the hydrocarbon contaminant.

One conclusion that could be discerned from this is that, if the surfacearea of the hydrocarbon contaminant was increased, the rate ofbiological activity would also increase. The apparatus used for thatpurpose in the subject invention very actively disperses the hydrocarboncontaminant throughout the soil matrix. The apparatus, known as the HHSYSTEM 614 Turborator, is manufactured by Frontier Manufacturing Companyand is capable of increasing surface area by a factor of at least about1×10⁶ with one two-way mixing pass. This same mixing action can disperseall of the soil amendments in the same manner. No other soil mixingmachine currently in use is capable of this type of mixing. The HHSYSTEM 614 Turborator does not just "mix" the soil; it literallyhomogenizes and aerates it. With this corresponding increase in surfacearea, the biological degradation rate will increase by several thousandtimes. This process is defined, for purposes of this invention, as"microenfractionation".

After all additions are added with the exception of bacteria (bacteriashould be added 24 hours after other additions for maximumsurvivability), microenfractionation needs to take place. For example,after application of nutrients and chemicals using a spray system suchas the HH System 1000 sprayer, then an apparatus, such as the HH SYSTEM614 Turborator, can start its work. In order to achieve the maximumeffect, the microenfractionating apparatus preferably must be passedthrough the soil matrix at least twice. The most efficient method is forthe machine to pass through the soil in one direction, then, turn on itsaxis and pass through the soil in the opposite direction. This way thesoil displacement (longitudinally) is essentially negated.

Stirring intervals for the contaminated soil will depend on the rate ofbiological activity. As the bacteria metabolizes, it uses up oxygen.When the oxygen is depleted, the biological system will switch toanaerobic digestion (inefficient and undesirable) until additionaloxygen is available. If the biological activity/rate of metabolism isvery high, frequent stirring intervals are warranted, possibly as muchas three stirring per week. If all of the treatment specifications areadhered to, very rapid biological metabolic rate will ensue. To keepthis activity at a high rate for the most rapid biological reduction ofpetroleum hydrocarbons, the extra stirring is required to aerate thesoil. Additional/more frequent nutrients and chemical requirements maybe necessary depending on the soil analysis/testing done as the projectprogresses.

The aerating capability of the subject microenfractionation system isvery important. First of all, it supplies and encapsulates air into thesoil pile for an oxygen source. It also purges the soil of carbondioxide at the same time. Carbon dioxide is produced during biologicaldegradation of petroleum hydrocarbon. Carbon dioxide concentrations inthe soil can lower the pH, and promote anaerobic conditions, both to thedetriment of biological systems.

In the past, machines such rototillers, trackhoes, discs, and the likewere used in remediation to "stir" contaminated soil. In the case oftrackhoes, for example, this procedure was extremely time consuming,frequently taking all day to stir 500 cu. yards of soil. This factoralone greatly limited the economics of attempting a large remediationsite. The soil handling would probably be cost prohibitive. While thismethod did a much better job of stirring than rototillers, it still didnot address the stirring problem completely. Ideally the soil should bevery thoroughly mixed with the soil amendments. The track hoe did nottotally address this. It was also too costly as well as inadequate inaerating the soil. Extensive research was done to find soil mixingequipment that would adequately address all of the requirements forefficient biodegradation of hydrocarbons. A variety of rototillers,track hoe attachments, pug mills, batch mixers and shakers wereresearched. While some of the machines identified had merit, dailymixing volumes were limited. Also, all of the machines were inadequatein aeration.

The HH System 614 Turborator mixes nutrients, bacteria, other amendmentsand contaminated soil into a treated microenfractionated material.Hydrocarbons will rarely contaminate soils in a uniform manner due tocauses ranging from varying soil permeability to the water insolublenature of hydrocarbons. Reducing the normally fractious nature ofhydrocarbon contamination in soils is a task that this apparatus canaccomplish very effectively. The mixing action simultaneously mixes thebacteria, nutrients and any other soil amendments with the hydrocarboncontaminated soil. This action brings the bacteria, nutrients and anysoil amendments into direct contact with the contaminated soil to allowthe most efficient biological system. The HH System 614 Turborator alsoaerates the soil very thoroughly as well as purging petroleumhydrocarbon degradation bi-products such as CO₂ from the soil to ensurethat the biological system remains in its most efficient aerobic mode.It is also much faster--it can "microenfractionate" 500 cubic yards ofsoil per hour rather than "stir" the 1000 cubic yards per day that thetrack hoe is capable of doing.

Referring now to FIGS. 1 and 2, a microenfractionating apparatus for usein the present invention is shown generally at 10. The apparatus 10includes frame 12 which is assembled from ladder-type left, right, andtop subframes, 12a, 12b and 12c respectively. In a two-wheel drivesystem, frame 12 is supported at its front end by left and right drivewheels 14 and 16, and at the rear by left and right caster wheels 18 and19. In a four-wheel drive system (not shown), left and right drivewheels are also provided at the rear of frame 12, and a similar drivesystem, as hereinafter described for driving drive wheels 14 and 16, isprovided to drive both the front and rear set of drive wheels. Eachwheel mounted on an axle is journaled into a supporting frame assembly40. Each rear caster wheel is mounted into its respective frame assembly40 by a vertical shaft journaled into frame assembly 40 as shown in FIG.3. Each rear caster wheel may be locked into a transverse position bylocking pin assembly 19 when desired as described below. Each frameassembly 40 includes an upright member 42 slidably received within acomplementary vertical sleeve 44 of a mounting assembly 46. Frameassembly 40 may thereby be raised or lowered relative to the ground onupright member 42 by actuation of hydraulic cylinder 43, allowing theground clearance of apparatus 10 to be raised or lowered duringoperation as more fully described below. Mounting bracket 46 is in turnpivotally mounted on frame 12 at brackets 48, allowing each frameassembly 40 and wheel to be pivoted by actuation of hydraulic cylinder45 for different modes of operation as described below. An alternativedesign for the wheel frame assemblies 40 is shown in FIGS. 4A and 4B.Note that in the alternative frame assembly design for drive wheels 14and 16, frame assembly 40 does not pivot, but rather is moved rearwardby hydraulic cylinder 45 and raised up by hydraulic cylinder 43 to itsstowed position.

As best seen by reference to FIG. 5, frame 12 includes upper deck 32 onwhich are mounted fuel tank 34, operator's cab 36, hydraulic oil tank37, engine 38, and hydraulic pumps 40, 42 and 44. As readily appreciatedby those skilled in the art, suitable auxiliary equipment for operationof the engine and drive components in dusty environments is alsoprovided, such as rotating self-cleaning screen 41 of the cooling systemof engine 38. Power for the operation of apparatus 10 is provided byhydraulic pumps 40, 42 and 44, which are driven by engine 38, preferablya 435 hp diesel engine such as Model NTH8559355, manufactured byCummins. Each hydraulic pump 40a and 40b, Sauer Sundstrand Series 90,Model 100, delivers pressurized hydraulic fluid to each of drum assemblydrive motors 48a and 48b to reversibly drive rotating drum and paddleassembly 22 from each end. Hydraulic pumps 42a and 42b deliverpressurized hydraulic fluid to left and right drive motors 50 and 52respectively. Pump 44a delivers pressurized fluid to hydraulic cylinders43 for raising and lowering frame 12, while pump 44b providespressurized fluid for operating hydraulic cylinders 45, and hydrauliccylinder 54 for raising and lowering tail section 31. Left and rightdrive motors 50 and 52 are separately controllable by the operator forsteering and for driving left and right drive wheels 14 and 16respectively through an appropriate drive assembly of a suitable designas could be readily determined by one skilled in the art.

In the preferred embodiment, a planetary gear assembly, Model No. W-3 asmanufactured by Fairfield is used on each the left side and right sidedrive wheel and motor assembly. The left side planetary drive assemblydiffers from that of the right side only in that it is rendered freewheeling for reasons described below by operation of an externalT-handle. Apparatus 10 is steerable and driveable forwardly, rearwardly,and sideways as described below by virtue of the fact that each drivewheel is driveable forwardly and rearwardly independently of the otherby appropriate hydraulic controls of standard design and well-known tothose skilled in the art.

The apparatus 10 exhibits an efficiency of operation resulting fromincorporation of a relatively long drum assembly, 17 feet or more forexample. Accordingly, the overall width of the apparatus 10 will be evengreater than the drum length, while the overall length of the frame ofthe apparatus is preferably no greater than 8'6". While providing moreefficient operation by requiring fewer passes to process a given amountof contaminated material, the overall width of prior art apparatusprevents them from being driven through standard fence gates betweenadjacent fields, and requires that they be transported over public roadsby truck and trailers designed for transporting heavy equipment. Thepresent invention overcomes these limitations and cost disadvantages ofprior art apparatus by providing for the first time a apparatus whichmay be driven sideways under its own power through standard fence gatesor over public roads for short distances, and which may be towed forlonger distances over public roads when necessary. The means ofconfiguring the present invention for so doing will now be described.

As described above and best seen by reference to FIG. 5, each wheel ismounted on a frame assembly 40 which is pivotable between a firstposition for accommodating forward and rearward travel of apparatus 10,and a second transverse position for accommodating sideways travel ofthe contaminated assembly 40 is moved between the first and secondpositions by a dedicated hydraulic cylinder 45, which is controlled bymeans of appropriate controls (not shown) from operator's cab 36.

Referring now to FIGS. 1 and 14, drum assembly 22 is mountedtransversely within chamber 24. Chamber 24 is an open-ended housingconsisting of a top wall 26, left and right side walls 28 and 30, andtail section 31 (FIG. 5). Front opening 25 is partially shrouded asshown in FIG. 1 by front drapes 33a-c. In the preferred embodiment,screened openings 23 are provided in left and right side walls 28 and 30ahead of drum 56 to permit additional air to be drawn into chamber 24during operation. Tail section 31, essentially a rearwardly extendingprojection of chamber 24, extends rearwardly from rear opening 27. Tailsection 31 may be described as a generally planar frame havingrearwardly and inwardly extending side members pivotally attached toframe 12 at one end, and to lateral member at their outer ends. Drapes39 are hung from each side member and the lateral member as best seen inFIG. 2. The drapes may be made from any suitable material. In thepresent embodiment, they are fabricated from grade 2 SBR in the form of5/16" thick conveyor belt material. Tail section 31 is pivotable byhydraulic cylinder 54 between a lowered operational position and araised stowed position for use during transport of the apparatus. Reardrapes 35 are hung from each side and the rear of tail section 31 andfrom angled frame members defining rear opening 27 as shown. Chamber 24serves to contain direct the air streams and contaminated materialduring operation of apparatus 10, and to reform the contaminatedmaterial into a windrow after mixing and aerating as more fullydescribed below.

Drum assembly 22 is journaled at opposite ends in left and rightsubframes 12a and 12b. Hydraulic motors 48a and 48b are mounted on leftand right subframes 12a and 12b, and reversibly drive drum assembly 22by means of shafts 49a and 49b when supplied with pressurized hydraulicfluid from hydraulic pumps 40a and 40b as described above. Drum assembly22 includes drum 56, a hollow cylinder having closed ends, onto whichare welded shafts 57a and 57b (not shown). Shafts 57a and 57b arejournaled into frame 12, and drivably connected with drum assembly drivemotors 48 as described above. Each of shafts 57a and 57b are journaledinto its respective subframe by means of a four bolt flange-type taperedroller bearing 91 such as Model FB 900 manufactured by Browning company.Each bearing 91 is fitted into a corresponding hole in left and rightsubframes 12a and 12b. A split ring collar 92 is fitted intocircumferential recesses 96 on each of shafts 57a and 57b, and bearsagainst the protruding rotating race 94 of the tapered roller bearing tocounteract spreading forces exerted on subframes 12a and 12b. Drum 56thereby functions as a tension member in frame 12 counteractingspreading forces represented in FIG. 7A by force arrows 102a and 102b.This novel use of drum 56 as a tension member saves the weight ofadditional structural members which would otherwise be required tocounteract spreading forces on subframes 12a and 12b, and allows a loweroverall height which further accommodates towing the compostingapparatus on public highways.

Turning now to FIGS. 8-12, a plurality of left and right paddles 58 and60 respectively, and center paddles 62 are mounted on the outercylindrical surface of drum 56 as shown. The paddles are preferablyarranged in four evenly spaced helical rows along the length of thedrum, each row traversing 90° about the drum from one end to the other.In a second embodiment shown in FIG. 9A, the paddles are arranged infour "V-shaped" rows. The V-shaped rows of paddles serve to eliminatetransverse steering torque on the composter which may be experiencedwith the use of helical rows where one end of the paddle row engages thecomposting material prior to the other. The V-shaped rows are orientedso that paddles at each end of the row engage the compost materialsimultaneously, eliminating any steering effect resulting from paddleson one end of the drum engaging the compost material before the other.Additionally, the paddles of each V-shaped row are offset from those ofadjacent rows to minimize bypassing of compost material past the drum.In one embodiment, the paddles in each row are spaced at 12" intervals.The corresponding paddles of adjacent rows are offset 3" from oneanother. Offsetting of the paddles in this manner promotes completemixing and aeration since the compost material at every point along theentire length of drum 56 is directly in the path of at least one paddle.

It is to be understood that more or less rows of paddles may be used.Left and right paddles 58 and 60 are mounted generally to the left andright of the center point of the drum respectively, while center paddles62 are mounted along a central portion of the drum. Center paddles 62are preferably interspersed with the left and right paddles alongportions of the drum as shown in FIG. 9. Minor variations in the numberand arrangement of center paddles interspersed with left and rightpaddles are possible in accordance to the present invention.

Each paddle has a base section 64 by which it is pivotally attached tobracket 66, which in turn is welded to drum 56 as shown in detail inFIG. 13. Each paddle is additionally secured in position by a shear pin68 inserted into hole 70. Shear pin 68 serves to release the paddle topivot rearwardly if impacted by a solid object during rotation of drumassembly 22. A deflector plate 71 is attached at a rearward angle to aforward edge of bracket 66. Each paddle includes a cutting edge 72formed on the leading edge of paddle body 74. Extending transverselyfrom the trailing edge of left and right paddles 58 and 60 is a singlepaddle portion 75 extending inwardly toward the longitudinal center ofdrum 56. Center paddles 62 each have a pair of opposed paddle portions78 extending outwardly toward opposite ends of drum 56. The paddleportions are preferably disposed at an angle slightly less thanperpendicular relative to the paddle body. Each paddle portion serves togenerate an air stream directed upwardly of the drum and in thedirection of the free end of the paddle when the drum is rotated in adirection such that the paddle travels upwardly and then rearwardly inits circular path around the drum. Stated slightly differently, thenormal direction of rotation of the drum assembly is in the oppositedirection of wheel rotation when the apparatus is being driven forward.

Having described the construction of the preferred embodiment, itsoperation will now be explained. The primary function of apparatus 10 isto microenfractionate the contaminated material. Referring now to FIGS.4 and 6, to configure the apparatus for being driven sideways, eachhydraulic cylinder 43 is activated to lower frame 12 onto the ground andto raise each wheel several inches above the ground. Tail section 31 isretracted to its raised stowed position by hydraulic cylinder 54. Eachframe assembly 40 is pivoted to its transverse position as shown in FIG.6; left and right drive wheels 14 and 16 are thereby alignedtransversely, as are left and right rear caster wheels. Left drive wheel14 is then drivably disengaged from left drive motor 50 by pushingT-handle 76 inward to disengage the planetary gear drive as discussedabove. Each hydraulic cylinder 43 is then activated to lower each wheeland raise frame 12 above the ground. Apparatus 10 is now configured forbeing driven sideways. It is propelled in this configuration by rightdrive wheel 16, now facing in the direction of "forward travel", whichby virtue of being fitted with flexible hydraulic supply and returnlines is operable in the transverse position. Steering is accomplishedby operation of hydraulic cylinder 45 to "swing" right drive wheel 16slightly as required to adjust the direction of travel. After arrivingat the desired location, the apparatus is reconfigured to its apparatusmode by reversing the foregoing procedure.

If it is necessary to transport the apparatus a greater distance, asecond transporting configuration is provided which allows the apparatusto be flat-towed by a truck. As before, each wheel is raised above theground, pivoted to its transverse position, and the wheels lowered,raising frame 12 above the ground. Left drive wheel 14 is drivablydisengaged as before, and left rear castor is locked against castoringaction by pin assembly 19. As best seen in FIG. 7, a pair of auxiliarytowing wheel assemblies 80a and 80b are then mounted on the right sideof frame 12 by being inserted into channels 82a and 82b, and yokes 84aand 84b respectively, and secured therein by locking pins 86. Auxiliarytowing wheel assemblies 80a and 80b are additionally secured by laterallink 86 which is pinned into bracket 88 and frame 12 as shown. Rightside drive wheel 16 and right rear castor 20 are then raised to lowerthe right side of frame 12 onto towing wheel assemblies 80a and 80b. Asshown in FIG. 2, fifth-wheel assembly 90 is an articulated, hinged frameassembly which is normally stored in a retracted position, and which isextended and locked into position as shown in FIG. 7 for being hooked toa truck (not shown) for towing apparatus 10. Fifth-wheel assembly 90 maybe raised and lowered by any suitable winch assembly 92 (FIG. 6).Apparatus 10 thus configured may be conveniently towed over public roadswith considerably less expenditure of time, effort and expense whencompared to prior art apparatus. Towing the composter is furtheraccommodated by the novel frame design of the present invention in whichdrum 56 serves as a tension member interconnecting vertical subframes12a and 12b as discussed above. The use of drum 56 as a tension memberin frame 12 eliminates the need for additional structural members toresist spreading forces exerted on subframes 12a and 12b duringoperation and towing. Frame 12 can therefore be designed with a loweroverall height to accommodate passage beneath lower bridges andoverpasses. Upon arriving at its destination, towing wheel assemblies80a and 80b are removed and apparatus is reconfigured for operation byreversing the above procedure. In the alternative embodiment, wheelassembly 81 is retracted by operation of hydraulic cylinder 83.

Prior art apparatus have proven generally unsatisfactory for processingsuch contaminated material due to their inability to effect adequateaeration of the materials to ensure aerobic conditions throughout thematerial, and due to their inability to effect adequate removal ofexcess moisture from the material when required. Applicants havediscovered a solution to these problems in the form of the presentinvention wherein a novel drum and paddle assembly 22 is rotated at highspeed in a direction opposite to that of prior art apparatus. Inaddition to directly impacting the contaminated material for shreddingit, the rotating drum assembly 22 also draws air from ahead of theapparatus into chamber 24 and generates a high-speed stream of air inchamber 24. The high speed air stream entrains the contaminatedmaterials and circulates them in overlapping, counter-rotating circularpatterns within chamber 24 for thoroughly aerating and mixing them. Theentrained materials are suspended and circulated in the air streams, andthen redeposited in a windrow to the rear of the rotating drum. As afurther advantage, after mixing and aerating the contaminated materialsas described, the present invention redeposits the materials in arelatively tall, more squared-off windrow having a higher volume ofmaterials per unit of surface area than known apparatus.

To begin a contaminated materialing operation, engine 38 is started, anddrum drive motors 48a and 48b are engaged to counter-rotate drumassembly 22, preferably at approximately 550 RPMs. Apparatus 10 is nowraised or lowered to a desired ground clearance by activation ofhydraulic cylinders 43. By so doing, apparatus 10 can be adjusted toprocess more or less material. This unique ability of the presentinvention allows for a more efficient contaminated materialing operationby permitting greater volumes of material to be formed into a singlewindrow and processed in a single pass, resulting in more efficient useof the available ground area, and less processing time for a givenamount of material. The height adjusting ability is additionally usefulin that as the contaminated materialing process partially decomposes thewindrow of material, the volume of material decreases. The presentinvention allows the operator to readily adjust for the volume decreasewithout any decrease in the effectiveness of mixing and aeration.

Having selected the appropriate height, the Operator now drivesapparatus 10 forward to engage the contaminated material. As theapparatus engages and proceeds along the windrow, the contaminatedmaterial is mixed and aerated by the action of the counter-rotating drumassembly. We define counter-rotation to mean rotation in acounterclockwise direction when viewed from the right end of the drumassembly, or stated slightly differently, in the opposite direction ofrotation of forward rolling drive wheels 14 and 16. Counter-rotatingdrum assembly draws air into chamber 24 from ahead of the apparatus inthe form of an upwardly and rearwardly directed air stream ahead of thedrum assembly, providing significant advantages as will be furtherexplained. As apparatus 10 approaches, the upwardly flowing air streamfirst engages the windrow ahead of the drum assembly and entrains aportion of the material which travels in the air stream and which doesnot directly engage the counter-rotating drum assembly. Counter-rotatingdrum assembly 22 then engages the remaining material which is deflectedby deflector plate 71 toward cutting edge 72, where the material ismicroenfractionated, and then entrained in the air stream. While theprecise amounts of material are microenfractionated in each pass of theapparatus are not known with certainty, in the processing of grassstraw, for example, 3-4 passes through the contaminated material willnormally produce a thoroughly microenfractionated contaminated material.

Under certain operating conditions, particularly when processing heaviermaterials, drum 30 can be slowed and even stalled. Owing to thehydraulic coupling between the drum and engine, stalling of the drum canstall the engine as well. In the preferred embodiment, this problem isaddressed by monitoring the engine speed to detect slowing of the drum,and reducing power to the drive wheels when slowing of the drum isdetected. Reducing power to the drive wheels slows the forward progressof the composter through the windrow, thereby reducing the load on thedrum and allowing it to resume its normal operating speed. In thepreferred embodiment, the power to the drive wheels is first reduced byto 50% or normal, and if after no more than a few seconds the drum hasnot resumed its normal operating speed, further reducing power to thedrive wheels to 30% of normal. Once the drum has resumed normaloperating speed, the power to the drive wheels is increased to itsnormal level. In order to avoid lurching and resultant damage to thedrive mechanism, applicants have found that the power to the drivewheels must be resumed gradually rather than all at once.

Reducing and increasing the power to the drive wheels in response tochanges in the drum speed is achieved by means of electrical control ofthe hydraulic pumps which provide pressurized hydraulic fluid to theleft and right drive wheel hydraulic motors 42a and 42b respectively. Aschematic diagram of the control system is shown in FIG. 16. A manuallyoperated speed controller is provided for each of the two drive wheels.During normal operation, speed controllers 104a and 104b electricallycontrol the output of hydraulic pumps 40a and 40b responsive to movementof the speed controllers by the operator. When drum 30 (not shown inFIG. 16) slows, a corresponding slowing of alternator 102 triggers asignal to controller 100, a Sundstrand Mod.MCH22BL1844. In response,controller 100 reduces the voltage applied to speed controllers 104a and104b by 50%, which reduces the power to left and right drive wheelhydraulic motors 50a and 50b respectively by a corresponding amount. Ifwithin two seconds drum 30 has not resumed its normal operating speed,controller 100 further reduces the voltage to speed controllers 104a and104b to 30% of normal. In applicants' experience reduction of power tothe drive wheels to 30% of normal has been sufficient to overcome allbut the most severe stalling conditions.

Once drum 30 has resumed its normal operating speed, controller 100restores normal voltage to speed controllers 104a and 104b and normaloperation is resumed. Applicants have found that the control system asdescribed is so responsive that it is necessary to resume normal powerto the drive wheels gradually in order to avoid lurching of thecomposter and damage to the drive train. To that end, once the drum hasresumed normal operating speed controller 100 increases the voltage tospeed controllers 104a and 104b gradually over several seconds.

The entrained microenfractionated contaminated material is propelledupwardly and rearwardly in a pair of generally rotating vortex-likeairstreams. Each airstream rotates generally upwardly and outwardly fromthe center of the drum, and spirals toward the rear of chamber 24. Theairstreams overlap at their inner portions, providing repeated exchangeof entrained material therebetween. As the air streams begin to losetheir velocity, the microenfractionated contaminated material begins todrop out of the air stream and is redeposited into a windrow. Applicantshave discovered for the first time that this method ofmicroenfractionation solves the aforementioned shortcomings of prior artapparatus; namely, that is that the relatively light wastes of thisnature can be sufficiently aerated, mixed and dried as necessary bybeing entrained in and contacted with a relatively large volume airdrawn into a mixing chamber by a drum and paddle design according to thepresent invention.

The airstreams are generated according to the preferred embodiment bythe left, right and center paddles previously described. As best seen inFIG. 9 and 14, each row of paddles according to the present inventionincludes a group of paddles having paddle portions 76 facing towardopposite ends of the drum. As the drum is rotated, each paddle portion76 draws air into chamber 24 and generates a series of airstreamsflowing in the direction of the drum rotation and laterally outwardlytoward the end of the drum. The series of airstreams generated by thetwo group of similarly oriented paddle portions 76 combine to form apair of oppositely rotating airstreams, each of which is rotatingoutwardly and spiralling rearwardly within chamber 24. The interspersingof paddles having opposite facing paddle portions 76 near the center ofthe drum creates a region in which the oppositely rotating airstreamsoverlap. In the overlapping region, contaminated material iscontinuously exchanged between the airstreams, providing more thoroughmixing of the contaminated materials than has heretofore been possible.The microenfractionated contaminated materials remain entrained in theairstreams for a relatively long time, until the air stream slowssufficiently to cause the material to fall from the airstream. In thisway, the contaminated material is afforded an extended contact time foraeration and drying. As the airstreams spiral rearward, they exitchamber 24 through rear opening 27 and rear tail portion 31. Rear drapes35 serve to limit the rearward travel of the airstreams and anyentrained or thrown contaminated materials. Applicants have discoveredthat the microenfractionation of the present invention is significantlyenhanced by the use of tail section 31, which apparently serves topromote the formation and rearward extension of the rotating airstreams,extending the contact time between the air and contaminated materials.The ability of the present invention to provide extended, intersticialaeration of relatively light contaminated materials has not beenpossible with prior art apparatus, and represents a significant advancein the art.

A further benefit of the present invention over prior art apparatus isrelated to the large volume of fresh air which is continually drawn intochamber 24 and into intimate contact with the contaminated material.This feature is also of significant benefit when heavier materials whichmay not be readily entrained in the airstream, and which are mixedprimarily by being thrown upwardly and rearwardly due to contact withpaddle portions 76. Even so, with the large amount of air drawn intochamber 24 in the form of high-speed air streams, thesemicroenfractionated materials are contacted with significantly more airunder more effective aerating conditions than is possible with knownapparatus.

BIOREMEDIATION OF ALIPHATIC, POLYCYCLIC, AROMATIC & HETEROCYCLICHYDROCARBON COMPOUNDS & CHLORINATED COUNTERPARTS THEREOF

Aliphatic, polycylclic, aromatic, and heterocyclic hydrocarboncompounds, and their chlorinated counterparts, are well known soil andwater pollutants. Creosote and pentachlorophenol, for example, aregenerally associated with surface soils, water in treatment lagoons orevaporation areas, and ground water contaminated with leachate from theabove sources. Almost all of these compounds are associated with woodtreatment facilities. Bioremediation, the use of pollutant-degradingmicroorganisms to ameliorate contaminated materials, represents onemeans by which these sites may be restored to their original condition.

The ability of bacteria to break down compounds that are difficult todegrade is a function of their metabolic activities or pathways.Microbial strains possess complex biochemical pathways that allow themto use synthesized organic compounds. But when aromatic organiccompounds undergo substitution with chlorine atoms, the compounds becomevery difficult to degrade. However, if the compounds are completelymetabolized by microbial strains, usually only carbon dioxide, water,and chlorine are the end products.

For a compound to be degraded biologically under field conditions,several basic criteria must be met:

(1) An appropriate microbial community possessing the requisitecatabolic ability must be present (exposure to the chemicalcontaminant),

(2) Bioavailability of the substrate along with the organism-substrateinteraction.

(3) Environmental parameters such as temperature, redox potential,oxygen and nutrient availability, and moisture must be conducive togrowth of organisms.

Growth of microorganisms at the expense of the phenol and methyl-phenol(cresol) components of wood treating compounds will result in theproliferation of a diverse microbial population employing a variety ofdegradative pathways. Because of the convergent nature of pathways ofaromatic metabolism, development of a large and diverse microbialpopulation proficient in degrading phenolic compounds will furnish therequisite pathways for the later steps of degradation of PAH's,heterocyclic compounds and chlorinated aromatic compounds. Hence, PAH'sand chlorinated organic compound degradation is greatly enhanced bysimultaneous cresol degradation.

Various methods have been developed for increasing the rate ofdegradation, such as mixing, nutrients, etc. Since most environmentshave an indigenous population of oil degrading microorganisms that canmultiply rapidly under appropriate conditions, addition of seed bacteriaand/or seed fungii is usually of little value in stimulating cleanup.

TESTING SEQUENCE

Testing procedures will vary depending on the regulatory agencies andsite location, but under typical conditions a complete analysis forcontamination should be made on site opening and site closings. Controltest analysis should be limited to those contaminants that producediverse microbial population (cresol/phenol), and those contaminantsthat are slow degraders (phenanthrene/PCP) and fast degraders(naphthalene). This will allow the operator to determine the rate oftotal degradation of all compounds, at reasonable cost control criteria.

TOTAL TESTING PROCEDURES

The following is a list of various contaminates associated with creosoteand pentachlorophenol. Coal tar creosote is composed of approximately85% polycyclic aromatic hydrocarbons (PAH's); 10% phenolic compounds;and 5% N--S--O Heterocyclics. The following lists will cover anestimated 95% of the total creosote and include some of the more toxicchemicals present.

Polycyclic aromatic hydrocarbons such as naphthalene,2-methylnaphthalene, phenanthrene, anthracene, 1-methylnaphthalene,biphenyl, fluorene, 2,3-dimethylnaphthalene, 2,6-dimethylnaphthalene,acenaphthene, fluoranthene, chrysene, pyrene anthraquinone,2-methylanthracene, 2,3-benzofluorene, and benzopyrene; phenoliccompounds such as phenol, o-cresol, m-Cresol, p-Cresol,pentacholorophenol, 2,5-xylenol, 3,5-xylenol, 2,3-xylenol. 2,4-xylenol,2,6-xylenol, 3,4-xylenol, and 2,3,5 trimethylophenol; heterocycliccompounds such as H-heterocyclics, S-heterocylics, quinoline,isoquinoline, carbozole, 2,4-dimethyl-phyridine, acridine, aniline,2-methylquinoline, 4-methylquinoline, pyrrole, pyrrolidine,benzothiophene, dibenzothiophene; and O-heterocyclics such asdibenzofuran.

HALOGENATED HYDROCARBONS

Pentachlorophenol solutions, which are the most well known halogenatedhydrocarbon contaninants, are composed of a 5% mixture ofpentachlorophenol in either heavy fuel oil or light mineral oils, andthey are sometimes used in conjunction with various metal naphthenatessuch as copper and zinc naphthenates and tetrachlorophenol. Otherhalogenated hydrocarbons include chlorinated aromatics such aschlorobenzene, 1,2-dichlorobenzene, 1,3-dichlorobenzene,1,4-dichlorobenzene, and 1,2,4-trichlorobenzene, and halogenatedaliphatics such as chloroform, carbon tetrachloride, 1,2-dichloroethane,1,1,1-trichloroethane, 1,1,2,2-tetrachloroethane, tetrachloroethylene,bromodichloromethane, dibromchloromethane, bromoform, and1,2-dibromoethane.

Aerobic reactions are employed in accelerated bioremediation of thetreated contaminated material of the present invention as previously andas subsequently discussed. However, in the case of bioremediation ofhalogenated hydrocarbons, methanogenic reactions are employed eitheralone or in combination with aerobic reactions. Aerobic reactionscontemplate the use of oxygen and microenfractionation as the drivingforces. Methanogenic reactions are endothermically driven reactionsconducted without stirring and in the absence of oxygen. These reactionscan be conducted in sequence whereby the first step comprises O₂-supplying amendments and microenfraction, followed by a second step inwhich anaerobic amendments are added and the reaction is allowed toproceed endothermically.

MUNITIONS, EXPLOSIVES, PROPELLANTS & PYROTECHNICS

The treated contaminated material can be contaminated with other toxicmaterial, such as the toxic materials in munitions, explosives,propellants, rocket fuel and pyrotechnic materials. These toxicmaterials typically can include aromatic hydrocarbon materials includingtrinitrotoluene which is a hydrazine compound.

SOIL CONSISTENCY MICRO/MACRO ORGANISMS & PLANTS

The soil environment differs from one geographic location to another,and so the degradation of compounds in the soil varies in differentlocations. Bacterial metabolism of these compounds is affected by suchsoil factors as pH, temperature, oxygen content, nutrients, and depth.Typically, degradative microbes in the soil require a near-neutral pH, atemperature of 77-82 degrees F. and available free oxygen, since many ofthe enzymes involved in metabolic degradation are oxidative.

The degradation of the petroleum hydrocarbons, and therefore, soilrecovery time, appears to be influenced by such factors as theparticular fraction of hydrocarbon spilled, the soil type, and theclimate. Understanding these environmental factors gives insight intothe distribution of microorganisms and their function in fillingecological niches, which are essential for supporting productivity andmaintaining environmental quality of ecosystems.

Commensal relationships, synergism, enables microbial populations toreach higher densities in the rhizosphere (soil influenced by plantroots) than in root free soil, and plants exhibit enhanced growthcharacteristics as a result of interactions with rhizophere microbes.Mutualism relationships lead to evolution of new organisms and on up thefood chain producing a balanced eco system and food web.

In order to achieve this balance ecosystem and therefore, provide thebest possible food web, an optimum physical environment must be effectedfor the soil medium.

SOILS

Soil temperature depends upon absorption of solar radiation, reradiationfrom the surface, conductive and exchange with the air, heat flowwithin, and the heat capacity of the soil. Soil color an surface textureinfluence both absorption and reradiation. Organic residues on the soilsurface tend to warm faster an display a major role in soil temperature,by interception of incoming and outgoing radiation and reduction invelocity of air movement at the soil surface. Water contact is also amajor factor in both heat transfer and heat retention. Changes in soilwater content involves significant quantities of energy or latent heat.All of the above affect the temperature of soil which is so importantfor an optimum physical environment for microbes to plants.

Since the growth of plants, microorganisms, etc, require optimumphysical environment, the presence of organic materials profoundlyaffect these properties. The humus acts as binding agents importingstability to mineral particle arrangements of soil aggregates. Soilssupporting growing plants and organisms must have a matrix-plus-osmoticpotential ranging from -15 bars up to a fraction of -1 bar. If the soilis too wet, aeration becomes limiting. Soils with mostly fine pores tendto remain wet and to warm slowly. By adding compost to fine pore soils,both aeration and drying of soils is enhanced.

By affecting a balanced program of soil preparation, nutrient additionand aeration designed for optimum plant growth, microorganisms will alsobe under optimum condition to proliferate and degrade almost all of thepresent hydrocarbon based contaminates that abound in our environment.Soil degradation of organics produces gaseous carbon dioxide. It isdesirable to remove as much of the carbon dioxide in the soil aspossible. Carbon dioxide can be released through the permeable soilthrough the use of the method of the present invention. Once the carbondioxide is purged from the soil, plants can intake the carbon dioxideand metabolize same to oxygen. Oxygen is released in the areasurrounding the plants and is effectively used in the subjectbioremediation of treated contaminated material.

PHYTO-REMEDIATION

Bioremediation is typically the removal of soil contaminants such ascreosote, PCP's and PAH's which facilitates the detoxification of thecontaminated soil, using indigenous microbial populations. Inphyto-remediation, which is a form of bioremediation, appropriate plantspecies are selected for independent removal of metals, particularlyheavy metals, from contaminated material such as soil. "Accelerated"phyto-remediation comprises phyto-remediation which further employs theabove-described principles of accelerated bioremediation to removemetals from contaminated material using plant species introduced intothe microenfractioned treated contaminated material. The metals in themicroenfractioned treated contaminated material pass into the interticesof these plants by hyperaccumulation during the course of the growingprocess.

An example of accelerated phyto-remediation is the use of Anthoxanthumas the plant species in the removal of heavy metals such as zinc, lead,copper, chromium, mercury, nickel, cadmium, arsenic, barium, andselenium, from microenfractioned treated contaminated soil. Other plantspecies which can used in accelerated phyto-remediation includeDeschampsia (lead), Gremnaina doniana (lead), Stereochleuena cameronii(lead and copper), Festuca ovina (lead), and Ambrosia artemisfolia(lead, zinc and copper).

After the plant species have been grown it is harvested. Harvesting ofthe plant species typically includes recovering at least some of thehyperaccumulated metal by removing at least a substantial portion of themetal from the metal-contaminated soil. More specifically, it ispreferred that after the plant species including the hyperaccumulatedmetal have been harvested, that certain portions of thephyto-remediation process are repeated such as repeating the steps ofintroducing into the microenfractionated treated contaminated materialadditional plant species capable of removing metals therefrom, andharvesting the additional plant species including hyperaccumulatedmetal. The steps in the phyto-remediation sequence are generallyrepeated until the amount of metal remaining in the treated contaminatedmaterial does not exceed a predetermined level, such as the requisitegovernmental standards. In each of the treatment sequences it ispreferred that the soil be renutrified and reseeded in order to maximizethe effect of micoenfractionation. Thus, in many instances, the amountof metal remaining in the treated contaminated material can be reducedso that it is not greater than 5 ppm.

Preferably, after the plant species including hyperaccumulated metalhave been harvested, certain further steps are taken. These step caninclude incinerating the harvested plant species to produce anincinerated material, collecting the incinerated material, and disposingof the incinerated material.

Another method of remediating metals involves microenfractionating themetal-contaminated material and fixation of metals therein. In additionto providing an entraining air stream having a sufficient velocity forentraining the contaminated material therein, entraining thecontaminated material in the air stream, microenfractionating thecontaminated material, and discharging the microenfractionatedcontaminated material from the air stream into the surroundingenvironment. The metals are then fixated in the microenfractionatedcontaminated material so that the metals are substantially preventedfrom leaching into the surrounding environment. The fixating of themetals can occur by physically combining the microenfractionatedcontaminated material with a material which prevents leaching of themetals into the surrounding environment. For example, the fixating ofthe metals can comprise physically combining the microenfractionatedcontaminated material with a coating material by coating thereof whichprevents leaching of the metals into the surrounding environment.Typically, the coating material comprises Portland cement, andpreferably the coating material further includes wood fly ash. Fixatingof the metals can also comprise chemically treating the metals toproduce metal compounds which will not leach into the surroundingenvironment. For example, chemical fixation of the metals can comprisechemically treating the metals by oxidizing the metals to produce metaloxides which will not leach into the surrounding environment.

In the phyto-remediation process of this invention, the soil to beremediated is first treated with chemical and/or biological amendmentsfor degradation of contaminants therein, such as an appropriate nutrientformula chosen for metal removal based on the specific plants employed.For instance, for broad leaf or grass plant species, a nutrient formulais first determined by conducting a soil analysis. Soil analysisdetermines the NPK and micro-nutrient formulas. The nutrient formulasare dependent upon whether the plants being used in the acceleratedphyto-remediation process are broad leaf or grass plant species.

The contaminated soil treated with the nutrient formula is subjected tomicroenfractionation, in the manner provided above which includes thesteps of providing an entraining air stream having a sufficient velocityfor entraining the treated contaminated material therein, entraining thetreated contaminated material in the air stream, microenfractionatingthe treated contaminated material, discharging the microenfractionatedtreated contaminated material from the air stream, introducing into themicroenfractionated treated contaminated material biological amendmentsfor facilitating accelerated phyto-remediation thereof, introducing intothe microenfractionated treated contaminated material plant speciescapable of removing metals therefrom, and acceleratedlyphyto-remediating the treated contaminated material. In the case ofhyperaccumulating, for example, metal in the soil is removed therefrominto the intertices of the plant species during growing thereof therebyremoving at least a substantial portion of said metal from themetal-contaminated soil.

The plant species including the hyperaccumulated contaminants are thenharvested. After harvesting, the steps of introducing into themicroenfractionated treated contaminated material additional plantspecies capable of removing contaminants therefrom, and harvesting theadditional plant species including hyperaccumulated contaminants, arerepeated until the amount of contaminants remaining in the treatedcontaminated material does not exceed the requisite governmentalstandards. After the plant species including hyperaccumulatedcontaminants have been harvested, the steps of incinerating theharvested plant species to produce an incinerated material, collectingthe incinerated material, and disposing of the incinerated material.

Accelerated phto-remediation is typically accomplished in a multi-stepmicroenfactionation process. Thereafter, windrows of themicroenfractionated material are formed to facilitate thephyto-remediation process. The windrows are then seeded with theappropriate first growth plant for producing a selected species.Moisture level are maintained for proper plant growth. Typically, soilanalysis is conducted to determine the water holding capacity of thesoil. This will establish the amount of water that can be retained bythe soil. The water can be applied to the soil by sprinklingapplication.

During the summer or warmer months of the year, the windrows can be leftuncovered. However, during the winter or colder months, the windrowsshould be covered by portable greenhouses. This is typicallyaccomplished by covering the windrow with Loretex 1212 UV (1/2 circlesize preferably 18" wide by 8' tall) which is made to order depending onthe individual windrow dimensions.

The seeding rate is preferably at least two times the recommended rate.For example, for Ambrosia artemisfolia, this means about 60,000 peracre. As for the nutrients, they are generally added on a 21 day cycle.

When the first growth plants have grown to a predetermined size, theyare harvested with a machine or device, such as a sickle blade mower,which is capable of severing substantially the entire plant in a mannerwhich will allow it to remain intact. The crop of plants harvested isthen incinerated in a closed incinerator and the resultant ash producedthereby is accumulated a disposed of, typically in a land fill.

A second growth of the selected plants is then produced at a height ofabout 18 inches. The above-described first method for growing,harvesting and disposing of the selected plants is repeated, and soilresampled for heavy metal content. A this time it can be determinedwhether or not to change the plant species previously selected.

Subsequent planting should wait for a period of about two weeks. In anycase, the above procedure should be repeated until the amount of heavymetal contaminants in the soil does not exceed governmental (EPA, etc.)standards.

In a further method of removing contaminants from contaminated material,the microenfractionated treated contaminated material is discharged fromthe air stream using the process described above. Then, biologicalamendments are introduced into the microenfractionated treatedcontaminated material for facilitating accelerated phyto-remediationthereof along with plant species capable of removing contaminantstherefrom. The treated contaminated material is then acceleratedlyphyto-remediated by hyperaccumulating the contaminants therefrom intothe intertices of the plant species during growing thereof. In this way,at least a substantial portion of the contaminants from the contaminatedsoil are removed. The contaminants can comprise a radioactive materialin general, and more particularly it can comprise any one of fissionradioactive products and activation products from nuclear reactors, fuelelement dissolution radioactive products, and naturally occurringradioactive products. The fission products from nuclear reactors canpreferably comprise any one of Cs-137, Sr-89, Sr-90, I-129, Ru-103,Ru-106, Zr-95, Nb-95, Ce-141, Ce-144, H-3, and Tc-99. Moreover, theactivation products from nuclear reactors can comprise any one ofPu-239, Pu-240, Pu-241, Am-241, Co-60, Na-55a, Mn-54, and Hg-203. As forthe fuel element dissolution radioactive products, they typicallycomprise U-238. Finally, as for the naturally occurring radioactiveproducts, they can be any one of Cm-244, C-14, and Th-232.

EXAMPLE 1

This example demonstrates the effect of accelerated bioremediation whenthe method of the present invention is employed using an HH System 614Turborator microenfractionation apparatus.

    ______________________________________                                        Contaminant: #2 Heating Oil                                                   Sampling Results:                                                             ______________________________________                                        Starting Sample                                                               Site UB 1-7-9           2,400 ppm                                             Ambient Air Temp        1.4° C.                                        Pile Temp, Sit UB 1-7-9 18.3° C.                                       First Sampling (55 days later)                                                Site UB 1-7-9           110 ppm                                               Ambient Air Temp        0.6° C.                                        Pile Temp, Site UB 1-7-9                                                                              13.7° C.                                       ______________________________________                                    

Procedure Used:

1. Soil sample for this site was measured for pH physicalparameters/soil moisture retention, water content and bulk density.

a. Physical soil parameters/grain size distribution.

b. Nutrient and micronutrient content.

2. Site was then windrowed and most of the large rocks were removed.

a. Windrow was laid out 4.2 meters wide and 1 meter to 1.8 meters high.

b. The site contained about 230 cubic meters of contaminated soil.

c. 30 cubic meters of alder sawdust was added to the 230 cubic meterpile.

3. The pile was then sprayed with a combination of HH MICRO-2, HHMICRO-51D, SIMPLE GREEN, AGRI-SC and water. SIMPLE GREEN, which ismanufactured by Sunshine Maker's, Inc. of Huntington Harbour, Calif., isa trademarked proprietary surfactant which acts as a degreaser andindustrial cleaner which is water soluble and comprises a gylcol ether,i.e, it contains up to 6% of 2-butoxyethanol (Butyl Cellosolve) and hasa nutrient content of <1.0% nitrogen by weight, 0.3% by formula ofphosphorus, and 0.6% by weight of sulfur. AGRI-SC is a tradmarked ionicsurfactant (a sodium lauryl sulfate derivative) marketed by Four StarAgricultural Services, Inc. of Bluffton, Ind., which functions as a soilchange potential modifier. After application of nutrients and chemicalsusing a spray system such as the H & H System T spray, then themicroenfractionation apparatus can start its work.

4. The pile was then microenfractionated with the HH SYSTEM 614Turborator two times.

5. Then the pile was covered with clear plastic.

The soil at the site was extremely difficult to work with. It had a claycontent of 27% and a silt content of 36% giving it an "almost fattyclay" description with 63% fines.

Alder sawdust with a particle size of 0.5 cm. in diameter was mixed intothe soil. This allowed the oxygen to become encapsulated into thetreatment pile. The HH SYSTEM 614 Turborator not only intermixed thesawdust almost completely, but it also forced oxygen into the pile andencapsulated it in the treatment site.

This example demonstrates that the method of the present invention, andthe method of using the subject apparatus, reduced the hydrocarboncontaminant level (#2 heating oil) in the contaminated material by 92.7%in 55 days at ambient temperature conditions of slightly above freezing.

EXAMPLE 2

The method of EXAMPLE 1 was repeated at the same location but at adifferent site. The conditions under which the test was conducted wereas follows:

    ______________________________________                                        Contaminant: #2 Heating Oil                                                   Sampling Results:                                                             ______________________________________                                        Starting Sample                                                               Site B-2          2,400 ppm                                                   Ambient Air Temp  1.4° C.                                              Pile Temp, Site B-2                                                                             12.8° C.                                             First Sampling (56 days)                                                      Site B-2          53 ppm                                                      Ambient Air Temp  0.6° C.                                              Pile Temp, Site B-2                                                                             7.9° C.                                              ______________________________________                                    

This example demonstrates that the method of the present invention, andthe method of using the subject apparatus, reduced the hydrocarboncontaminant level in the contaminated material at a second site at thesame location by 97.8% in 56 days at ambient temperature conditions ofslightly above freezing.

EXAMPLE 3

    ______________________________________                                        Contaminant:   #2 Heating Oil at Low Levels                                   Starting Date: December 1, 1992                                               ______________________________________                                    

Description:

The contaminant on this site was #2 heating oil at low levels--i.e.,less than 2,000 ppm average. The soil type was silt mixed with clay. Twoseparate dirt piles of approximately 300 cubic yards each represent thematerial to be treated.

Procedure Used:

The treatment regiment for both sites was the same with one exception.The dirt pile in the lower parking lot had an additional amendmentadded.

Because of the dense nature of the soil, wood sawdust (non cedar) wereadded to the contaminated soil as a bulking agent to allow air pocketsfor the required oxygen the bacteria need for aerobic digestion of thehydrocarbons.

Ideally, the underliner would have been installed first, then wood chipsdistributed and compacted to 18" in depth uniformly over the liner.Next, the soil would be installed on top of the wood chips. In this casehowever, the soil was already installed on the underliner, hence thewood chips were applied to the top of the soil pile. After this step,the nutrient/surfactant application commenced. This was facilitated bythe use of a spray boom using agricultural components to achieve evendistribution over the soil pile. A combination of HH MICRO-51D, HHMICRO-2D, Simple Green and Potassium Hydroxide for pH neutralizationwere specified for this biological degradation.

Mixing of the soil piles was accomplished by utilizing the HH SYSTEM 614Turborator soils mixer. Two passes through the soil pile were requiredto adequately mix the nutrients and wood chips into the soil.

Weather conditions during treatment were cold -4° to 0° C. Ordinarily,these low temperatures are not conducive to biological treatment ofsoils. However, at twenty-four hours past treatment, temperatures ashigh as 26° C. were recorded within the soil piles. This rapid rise insoil temperature is most likely to increase biological activity in soilpiles. NOTE: Soil piles were covered with clear visqueen. Loretex 1212UV is ordinarily recommended for this purpose.

By utilizing the HH SYSTEM 614 Turborator for soil homogenization, thesoil piles can be significantly larger than ordinary land farm programs.The soil pile profile can be 14 ft. wide at the base, 5 ft. wide at thetop, 6.5 ft. high. Length is determined by the quantity of soil or spaceconstraints at the site. The HH SYSTEM 614 Turborator homogenizes thesoil extremely well while also aerating the pile with fresh air andpurging CO₂ from the soil.

The combination of H&H nutrients, Simple Green and SYSTEM 614 greatlyenhance the speed of biological degradation. These soils piles werebeing land farmed by conventional methods for several months prior tothe H&H Eco Systems' treatment and only showed a hydrocarbon reductionof approximately 2%.

This example demonstrates that the method of the present invention, andthe method of using the subject apparatus, reduced the hydrocarboncontaminant level of the hydrocarbon material (heating oil) in thecontaminated material by 94.5% in 55 days during winter weather andtemperatures in the months of December and January.

EXAMPLE 4

This example demonstrates the effect of accelerated bioremediation on aparticularly difficult hydrocarbon contaminant (used motor oil) when themethod of the present invention is employed using an HH System 614Turborator microenfractionation apparatus.

    ______________________________________                                        Contaminate: Used Motor Oil                                                   Sampling Results:                                                             ______________________________________                                        First Sampling:                                                               TPH level:             35,000 ppm TPH                                         Second Sampling (32 days later):                                              TPH level:             13,000 ppm TPH                                         Ambient Air Temperature:                                                                             1.6° C.                                         Pile Temperature:      24.4° C.                                        Third Sampling Date (68 days later):                                          TPH level:             880 ppm TPH                                            Ambient Air Temperature:                                                                             1.6° C.                                         Pile Temperature:      15.5° C.                                        ______________________________________                                    

Procedure Used:

a. Site was lined with NOVA-THENE® RB616-6HD.

b. The liner was then covered with an 8×14 ft. wide pile of contaminatedsoil.

c. A layer of alder dust 18" in depth (compacted) was added to the pile.

d. Contaminated soil was then placed in a windrow 14 ft. wide and 5-6ft. high

e. Site was then sprayed with the following:

150 L. HH MICRO-51

100 L. HH MICRO-2

51 L. Simple Green

457 L. Water

f. Pile was then microenfractionated twice using an HH SYSTEM 614Turborator.

g. Pile was then covered with Loretex 1212 UV to allow solar radiationrays to penetrate.

h. Pile was left untouched for 32 days at which time the following wasdone:

The cover was removed

The site was again sprayed with

150 L. HH MICRO-51D

100 L. HH MICRO-2

51 L. Simple Green

457 L. Water

Again, the pile was microenfractionated twice with HH SYSTEM 614

Pile was recovered with Loretex 1212 UV.

i. Pile was left untouched for an additional 36 days at which time thefollowing was done:

The cover was removed

The site was sprayed with

150 L. HH MICRO-51D

51 L. Simple Green

557 L. Water

The pile was microenfractionated twice with HH SYSTEM 614.

j. Pile was recovered with Lortex 1212 UV

This example demonstrates that the method of the present invention, andthe method of using the subject apparatus, reduced the hydrocarboncontaminant level of a difficult-to-bioremeditate hydrocarbon material(used motor oil) in the contaminated material by 97.5% in 68 days atambient temperature conditions of slightly above freezing.

Having illustrated and described the principles of my invention in apreferred embodiment thereof, it should be readily apparent to thoseskilled in the art that the invention can be modified in arrangement anddetail without departing from such principles. I claim all modificationscoming within the spirit and scope of the accompanying claims.

We claim:
 1. A method of using an apparatus in the acceleratedbioremediation of a hydrocarbon-containing contaminated material whichhas been combined with chemical and/or biological amendments to form atreated hydrocarbon-containing contaminated material, the methodcomprising the steps of generating an air stream at a velocitysufficient for entraining the treated hydrocarbon-containingcontaminated material therein, entraining the treatedhydrocarbon-containing contaminated material in said air stream, andmicroenfractionating the treated hydrocarbon-containing contaminatedmaterial under conditions sufficient to form a microenfractionatedtreated hydrocarbon-containing contaminated material therebyfacilitating subsequent accelerated bioremediation under conditionssufficient for conducting said accelerated bioremediation.
 2. The methodof claim 1, wherein the treated hydrocarbon-containing contaminatedmaterial comprises a hydrocarbon-containing material selected from agroup consisting of a polycyclic and chlorinated polycyclic, an aromaticand chloroaromatic compound, a heterocyclic and chlorinated heterocycliccompound, and an aliphatic and a chloroaliphatic compound.
 3. The methodof claim 1, wherein the hydrocarbon-containing material selected from agroup consisting of phenol, cresol, pentachlorophenol, phenanthrene andnaphthalene.
 4. The method of claim 1, wherein the acceleratedbioremediation is conducted aerobically or methanogenically.
 5. Themethod of claim 1, which further includes the step of, aftermicroenfractionating the treated contaminated material to form amicroenfractionated treated hydrocarbon-containing contaminatedmaterial, locating a cover over the microenfractionated treatedhydrocarbon-containing contaminated material, the cover allowingsubstantial solar radiation to pass therethrough and into themicroenfractionated treated hydrocarbon-containing contaminatedmaterial, thereby facilitating the accelerated bioremediation andpreventing moisture from soaking the microenfractionated treatedhydrocarbon-containing contaminated material.
 6. The method of claim 1,wherein a treated hydrocarbon-containing contaminated materialentraining air stream is generated by the apparatus which comprises anelongate drum having a longitudinal axis, first and second end portions,and a center portion, the drum being rotatable about its longitudinalaxis at a rotational speed, and means extending outwardly from the drumfor generating the treated hydrocarbon-containing contaminated materialentraining air stream.
 7. The method of claim 6, wherein the treatedhydrocarbon-containing contaminated material entraining air streamcomprises a plurality of air currents, and wherein the means extendingoutwardly comprises an air current generating means comprising aplurality of paddles extending outwardly from a cylindrical outersurface of the drum.
 8. The method of claim 7, wherein each paddlecomprises a base portion connected to the drum, and a blade portion,each blade portion having a major surface oriented for generating atleast one air current having a sufficient velocity for entraining andtransporting the treated hydrocarbon-containing contaminated materialupwardly of the rotating drum when a drum is rotated at a rotationalvelocity.
 9. The method of claim 1, wherein the treated contaminatedmaterial entraining air stream comprises a plurality of intersecting aircurrents, each of the intersecting air currents having a sufficientvelocity for entraining and transporting a portion of the treatedcontaminated material upwardly of the apparatus.
 10. The method of claim9, wherein the apparatus used for generating a plurality of intersectingair currents is provided which comprises:a plurality of end paddlesextending radially outwardly from first and second end portions of adrum, each of the end paddle comprising a base portion connected to thedrum and a blade portion, the blade portion having a major surfaceoriented relative to the drum for generating an air current directedupwardly of the drum and transversely toward the center portion of thedrum when the drum is rotated at a rotational speed; a plurality ofcenter paddles extending radially outwardly from the center portion ofthe cylindrical outer surface, each of the center paddle comprising abase portion connected to the drum, and a blade portion having first andsecond major surfaces, the first and second major surfaces orientedrelative to the drum for generating an air current directed upwardly andrearwardly of, and transversely toward the first and second end portionsof the drum respectively when the drum is rotated at the rotationalspeed; and the air currents generated by the end and center paddlesintersecting and combining to form the treated hydrocarbon-containingcontaminated material entraining air stream for microenfractionating andhomogenizing and aerating the treated hydrocarbon-containingcontaminated material.
 11. The method of claim 1, wherein the treatedcontaminated material entraining air stream comprises a vortex-type airstream which transports the entrained treated contaminated material in agenerally circular path.
 12. The method of claim 10, wherein the end andcenter paddles extend radially outwardly from the drum and are arrangedin a plurality of helical longitudinal rows.
 13. The method of claim 7,wherein the drum further comprises first and second transition portionsdisposed between the center portion and the first and second endportions respectively, the first and second transition portions of thedrums having a plurality of end paddles and a plurality of centerpaddles extending radially outwardly therefrom.
 14. The method of claim1, wherein at least about 70% of a total amount of hydrocarbon materialin the treated hydrocarbon-containing contaminated material isremediated within 120 days of treating the treatedhydrocarbon-containing contaminated material with the chemical and/orbiological amendments.
 15. The method of claim 1, wherein themicro-enfractionating step further comprises homogenizing and aeratingthe treated contaminated material.
 16. The method of claim 1, whereinthe step of microenfractionating the treated hydrocarbon-containingcontaminated non-microenfractionated material increases the surface areaof said treated hydrocarbon-containing contaminatednon-microenfractionated material, as compared to the surface area of thetreated hydrocarbon-containing contaminated non-microenfractionatedmaterial, by a factor of at least about 1×10⁶.
 17. The method of claim1, which further includes the step of discharging themicroenfractionated treated contaminated material from the air streamand redistributing it throughout a soil matrix thereby substantiallyincreasing the surface area of the microenfractionated treatedcontaminated material.
 18. The method of claim 17, which furtherincludes the step of dispersing further chemical and/or biologicalamendments throughout the redistributed microenfractionated treatedhydrocarbon-containing contaminated material.
 19. The method of claim 1,wherein the chemical and/or biological amendments are organic materials.20. The method of claim 1, which further includes the step of locatingan impervious undercover below the treated contaminated material priorto the microenfractionating step thereby preventing the chemical and/orbiological amendments from leaching into soil underlying the treatedcontaminated material.
 21. The method of claim 1, wherein said treatedhydrocarbon-containing contaminated material entraining air stream isconducted in an air stream containing chamber which comprises a frontwall, an opposed side wall, and an air inlet opening formed in saidfront wall, or in one or more of said opposed side walls.
 22. The methodof claim 1, wherein said treated contaminated material entraining airstream is conducted in an air stream containing chamber which comprisesa front wall and an air inlet opening formed in said front wall.
 23. Themethod of claim 7, wherein said paddles extending radially outwardlyfrom said drum are arranged in a plurality of V-shapedlongitudinally-extending rows.
 24. The method of claim 7, wherein firstand second drum end portions are journaled in respective frame sides,said first and second end portions adapted for resisting a force actingto spread said opposing frame sides.
 25. The method of claim 7, whereinsaid drum includes a first and second end portion each including athrust bearing mounted outboard of a respective opposing frame side, andeach thrust bearing adapted for rotatably bearing on an outboard surfaceof its respective opposing frame side to resist a force acting to spreadthe opposing frame sides.
 26. The method of claim 7, wherein said paddleon a rotatable drum comprises:a body having a first planar portionhaving a leading edge; and having a second planar portion connected at afirst angle to the first paddle portion, the second planar portionoriented so as to engage contaminated material with a planar surfacewhen the rotatable drum is rotated; and mounting means connected to thebody for mounting the paddle onto said elongate drum.
 27. The method ofclaim 26, wherein said paddles further comprise a third planar portionconnected at a second angle to the first paddle portion, the thirdplanar portion adapted for engaging contaminated material with a planarsurface when the rotatable drum is rotated.
 28. The method of claim 7,wherein said paddles comprise mounting means including a base portionhaving first hole for receiving a paddle attachment bolt and a having asecond hole for receiving a shear pin.
 29. In a method of acceleratedbioremediation for treating hydrocarbon-containing contaminatedmaterial, wherein said hydrocarbon-containing contaminated material istreated with chemical and/or biological amendments, the improvementwhich comprises:a. providing said treated hydrocarbon-containingcontaminated material; b. providing an entraining air stream having asufficient velocity for entraining the treated hydrocarbon-containingcontaminated material therein; c. entraining the treatedhydrocarbon-containing contaminated material in the air stream; d.microenfractionating the treated hydrocarbon-containing contaminatedmaterial; and e. discharging the microenfractionated treatedhydrocarbon-containing contaminated material from the air stream foracceleratedly bioremediating the treated hydrocarbon-containingcontaminated material under conditions sufficient for conducting saidaccelerated bioremediation.
 30. The method of claim 29, wherein the stepof providing an entraining air stream comprises providing an entrainingair stream including a plurality of upwardly and transversely flowing,intersecting air currents.
 31. The method of claim 29, wherein theentraining air stream comprises a vortex-like entraining air stream. 32.The method of claim 29, wherein the step of providing an entraining airstream includes the step of rotating a drum assembly at a rotationalspeed sufficient for generating the entraining air stream, the drumassembly including means for generating a plurality of intersecting aircurrents when rotated.
 33. The method of claim 29, wherein theaccelerated bioremediation purges CO₂ from, and aerates the treatedhydrocarbon-containing contaminated material.
 34. The method of claim29, wherein the volume of treated contaminated material which isacceleratedly bioremediately treated is at least about 1500 cubic yardsper day per apparatus.
 35. The method of claim 29, which furtherincludes the step of adding wood particles to the treated contaminatedmaterial prior to the microenfractionating step.
 36. The method of claim29, wherein the microenfractionating step comprises homogenizing andaerating the treated contaminated material.
 37. The method of claim 29,which includes the step of microenfactionating treatedhydrocarbon-containing contaminated non-microenfractionated materialthereby increasing the surface area of said treatedhydrocarbon-containing contaminated non-microenfractionated material, ascompared to the surface area of the treated hydrocarbon-containingcontaminated non-microenfractionated material, by a factor of at leastabout 1×10⁶.
 38. The method of claim 29, wherein the average ambienttemperature during the accelerated bioremediation of the treatedcontaminated material is not more than about 10 degrees C.
 39. Themethod of claim 29, which further includes the step of redistributingthe microenfractionated treated contaminated material from the airstream throughout a soil matrix thereby substantially increasing thesurface area of the microenfractionated treated contaminated material.40. The method of claim 37, which further includes the step of furtherdispersing the chemical and/or biological amendments throughout theredistributed microenfractionated treated contaminated material.
 41. Themethod of claim 29, wherein the chemical and/or biological amendmentsare organic materials.
 42. The method of claim 29, which furtherincludes the step of, after microenfractionating the treatedhydrocarbon-containing contaminated material to form amicroenfractionated treated hydrocarbon-containing contaminatedmaterial, locating a cover over the microenfractionated treatedhydrocarbon-containing contaminated material, the cover including meansfor allowing substantial solar radiation to pass therethrough and intothe microenfractionated treated hydrocarbon-containing contaminatedmaterial and means for preventing moisture from passing therethrough,thereby facilitating the accelerated bioremediation while preventingmoisture from soaking through the cover and passing into themicro-enfractionated treated hydrocarbon-containing contaminatedmaterial.
 43. The method of claim 35, wherein the amount of woodparticles added to the treated hydrocarbon-containing contaminatedmaterial prior to the microenfractionating step is up to about 20% byvolume, based on the total volume of the treated hydrocarbon-containingcontaminated material.
 44. In a method of accelerated bioremediation fortreating hydrocarbon-containing contaminated material, wherein saidhydrocarbon-containing contaminated material is treated with chemicaland/or biological amendments, the improvement with comprises:a.providing said treated hydrocarbon-containing contaminated material; b.providing an entraining air stream having a sufficient velocity forentraining the treated hydrocarbon-containing contaminated materialtherein; c. entraining the treated hydrocarbon-containing contaminatedmaterial in the air stream; d. microenfractionating the treatedhydrocarbon-containing contaminated material employing amicroenfractionating apparatus; and e. discharging themicroenfractionated treated hydrocarbon-containing contaminated materialfrom the air stream for acceleratedly bioremediating the treatedhydrocarbon-containing contaminated material under conditions sufficientfor conducting said accelerated bioremediation, at least about 70% of atotal amount of hydrocarbon material in the treatedhydrocarbon-containing contaminated material being remediated within 120days of microenfractionating the treated hydrocarbon-containingcontaminated material, the volume of treated hydrocarbon-containingcontaminated material which is acceleratedly bioremediately treated isat least about 1500 cubic yards per day per microenfractionatingapparatus.